Looks like Tracfones are getting cheaper for the moment, and so are minutes...
First off, the Motorola v170 and LG 200c are both $20 at some stores.
Second, at CVS drugstores Tracfone's 60-minute cards are temporarily $15 apiece instead of $20, if you're looking for cheap service time.
For mroe info, see the Turk's post here (thanks!):