Sometimes it’s not so obvious that something will make a horrible holiday gift (or just a grudgingly accepted one). That’s why we’re here to clear the air for you. Following are 10 tech-related products, which, while potentially tempting, you might want to rethink before wrapping up in red and green (or blue and silver, or whatever the colors for your holiday of preference happen to be).They aren’t necessarily bad products, just not particularly apt choices for the holidays.

Note: This post is based on the CNET photo gallery “Holiday tech gifts we don’t recommend,” captioned by Caroline McCarthy. It’s also available as a PDF download.

#10: Pointless USB add-ons

We’ve had enough of these. Stupid gadgets that plug into your USB ports are not only a waste of space, they’re totally 2006–come on, USB 2.0 is no longer a novelty! So, for the sake of humanity, please don’t stuff stockings with USB rocket launchers (pictured), noodle strainers, aromatherapy humidifiers, and vibrating massage toys (err, OK) Your loved ones will thank you later.

#9: Leaf blower

Leaf blowers. They’d make great gifts, wouldn’t they? Your neighbor with the sloppy yard might really appreciate one of these Toro Electric Ultra Blowers, right?

Think carefully.

Yes, it might be great for keeping lawns tidy, but mark our words–you’re going to regret buying one of these as a gift for anyone who lives within a few hundred yards of your house. That is, unless you manage to invest in a set of high-end noise-canceling headphones for yourself and never take them off.

#8: Nose-hair trimmer

The nose hair trimmer is the gadget equivalent of fruitcake. It will never be a tasteful gift, ever. We’re not going to say any more on this one.

#7: Everki Plunge waterproof iPod case

We couldn’t skip this one–it is, so far, the lowest-rated product out of everything CNET Reviews has catalogued in the entire 2007 calendar year. Sure, this $19 iPod case will keep your music player dry, but unfortunately, it makes it unbelievably difficult to actually hear the sound that comes out. Kind of a bad thing.

CNET Reviews senior editor Donald Bell called the Plunge “a step up from a sandwich bag.” That’s probably telling.

#6: Anything with the “Digg crack code” on it

This past spring, social news site Digg soared to the top of mainstream news when the company refused to obey a Digital Millennium Copyright Act (DMCA) takedown notice concerning an HD DVD crack code that a member had posted on the user-powered news rankings. As a result, the “forbidden” code became the geek slogan du jour to toss on mouse pads, coffee mugs, boxer shorts, and just about anything else you can make on CafePress or Zazzle. Also getting in on the trend were tech-focused retailers like Think Geek, which still sells this T-shirt.

But we don’t recommend that you give any “Digg crack code” gear as presents this holiday season. First of all, only the most uber-tuned-in of tech enthusiasts would even understand this in the first place. And second, even if they did, their reactions would probably be something along the lines of, “That is so last year.” You’d be better off with “All Your Base Are Belong To Us,” which at least has some retro-chic appeal now.

#5: Options: The Secret Life of Steve Jobs, A Parody by Daniel Lyons

This is another instance of “only the geeks would get it.” The Secret Diary of Steve Jobs, a once-anonymous blog created by Forbes editor Daniel Lyons (under the pseudonym “Fake Steve Jobs”), was a runaway hit with the Techmeme set as it lampooned the iconic Apple CEO and all the people around him. Unfortunately, Fake Steve’s influence failed to reach very far outside Silicon Valley, and so the novelized version of the blog, published in November, has a narrow potential audience indeed.

Additionally, three CNET reporters who read Options agreed that the book just isn’t that good. It has its funny moments, but the plot doesn’t really work (especially considering that a shareholder lawsuit over Apple’s stock options mess was just dismissed), and some of the most hilarious characters from the Secret Diary, like Squirrel Boy (a.k.a. Google CEO Eric Schmidt) and Mr. Bigglesworth (Valleywag gossip blogger Owen Thomas) failed to merit any appearances in the novel.

So, yeah, skip this one. Get your favorite Apple geek some new iPod accessories instead.

#4: Motorized toothbrush

Motorized toothbrushes have been around for a while. This one sold by Hammacher Schlemmer is even ultrasonic. You might be tempted to grab one of these for a family member as a holiday gift that would actually be useful–it seems like a logical choice.

But stuff like this just makes an awkward gift. You never know who will open one of these and take it as a subtle statement of “your breath smells bad.”

Likewise, some people, upon receiving exercise equipment, will take it to mean “you’re fat.” Or “your feet smell” for one of those, uh, foot smell-reducers, or “you have a drinking problem” for a personal breathalyzer.

Best to steer clear of these unless you’re really confident about how it’ll be received. Heck, even a Roomba robot vacuum could be taken the wrong way by certain people-you know: “Not only are you a slob, but you’re lazy, too.”

#3: Anything HD DVD or Blu-ray

So maybe you have good reason to know that someone on your holiday shopping list is going to actually have use for HD DVD or Blu-ray products, whether they be the discs themselves or the hardware to play them–PlayStation 3 owners, for example (the Sony console comes with a Blu-ray player), or someone who’s actually taken the plunge and purchased an HD DVD or Blu-ray player (or the combo player that LG makes). But that’s the exception to the rule.

The ugly hi-def format wars unfortunately aren’t over yet. Maybe we’ll know by next year, but this is still enough of a toss-up that it probably merits holding back on the holiday gifts.

Plus, there’s always the awkward situation in which you thought your brother had a Blu-ray player, so you bought him the first season of Prison Break on Blu-ray, only to learn that he’s actually an HD DVD devotee. Oops.

#2: Windows Vista

Let’s face it. Anyone who actually wanted Vista already has it; the system’s been out for almost a full year now. The folks who don’t have it are either Mac or Linux users, or holdouts who’ve heard about the well-documented bugs in the system.

Moreover, operating systems are a total yawn. Who wants to get one of these as a holiday gift, anyway?

#1: Anything holiday-themed

So you’ve picked out a set of solar-powered Christmas tree lights, Hanukkah-themed iPod skin, $1,500 outdoor light-up display shaped like Santa Claus driving a golf cart (pictured), or some other gift that (you think) ties in nicely to the holiday season.

Well, guess what? By the time that special someone opens the gift up, the holidays are just about over, sucker! That is, unless your friend receiving the gift is one of those wackos who puts out Christmas decorations on 12/26 and leaves them up through July…and if that’s the case, we think you have weird friends.