I have been interested in formal methods for some time. I have used formal methods to reason about some very specific sub-areas of a few projects I have been working on. I was n
Belatedly adding to this thread... Eunsuk Kang has recently applied Alloy to perform security analyses of web APIs for some start ups (following many applications of Alloy in security such as Apurva's analysis of OAuth and Barth et al's analysis of browser based security mechanisms for CSRF etc); Pamela Zave has been working on an impressive analysis of Chord, a peer to peer storage system, and has recently written up a fix to the original algorithm.