I'm right there with you. I've always had a great love of nature and environmental sciences. In HS, I focused on my science workload, but also spent a lot of time working and playing with the school's computers. After that, I went to college, and got a BS in environmental policy/management. Being you're typicaly less-than-wealthy college student, I took a work-study job with the campus IT department...it seemed a natural fit. Well, I ended up working the help desk, and 4 years later I graduated with my BS, plus a wealth of self-taught/OTJ IT knowledge.
After graduating I worked for a financial company doing desktop application support, until I was hired by an environmental company several months later. Funny how things happen...my supervisor at my new job was also the IT guy. I got some side projects from him in addition to my environmental responsibilities. When he left, I got the role of LAN Admin. Spent the next 7 years splitting my time between IT and environmental field work, up until last April when I transferred to a different office to be the full-time LAN Admin. I still get to do the environmental work, so I"m happy on both fronts.
Moral of the story: I enjoy learning, and because I did a lot of learning on my own, I'm very successful in a job I love, with a great company.
OH...and one other reason I love IT: the blinking lights!