Wow, Thor IS da man!! Great eye!
Thanks for all the advice. There is a 2009.5 FS downtube on Yan's site for $399, but in the end, I found a bike on CL - it's a 2001 Dahon Zero G with a size L frame. It has upgraded handlebars & front fork with a sprung seat. I took it to LBS Lombardi Sports yesterday for their $35 commuter tuneup special & had new hybrid tires & tubes put on (the old ones felt like they had dryrot). $250 for the bike an $100 for the tuneup & tires and it's good to go.
Now to figure out what I'm supposed to wear for the commute. I have to wear a nice shirt and dress pants at my office, and don't want to get my work clothes all sweaty. I think I've seen guys cycling with a skinny garment bag over their shoulders, but I'm hoping to find a less bulky option, since I'll have to carry my laptop as well. Any ideas? Thanks!!