Recommendations for USB/Portable Mac password managers?

A management-level user that I deal with has recently gone from a Windows platform, to Mac only. He has been using RoboForm2Go, as he demands his password manager program be on his USB drive only. However, Roboform2Go only exists for Windows.

I am looking for recommendations for reliable Mac password managers that will work on a USB drive. He likes the functionality of Roboform2Go, but I can't find any indication that there will ever be a Mac version. So I am hoping there are others out there that some of you reading this might find laudable.