I second JoeP's comments on folding bikes. He gave a very good synopsis on the relative merits of the various folders. I'll add this about folding the bike Fridays, though. They make many different models, including recumbents, tandems, and even a bike that can be configured as either a tandem or a single. Almost all BF models "quick-fold" in seconds. In the quick-fold configuration, the bike can be put in a bag and carried, but it's nowhere near as small as you can get it through disassembly (in which you remove the front wheel, the seat post and the handlebars). I can disassemble my New World Tourist into it's suitcase in 15 minutes or less, so it isn't necessarily a 45 minute job as Joe indicated (although the first few times you do it, it could well take that long - it gets much easier and quicker with experience). Some of the other models - such as the air-glide and other "air" models with the suspension beam require more disassembly since the beam needs to be removed rather than folded. Contrary to Levities concerns about rigidity, the bike Fridays have excellent riding characteristics. Professional bike racers often use them as a training bike while traveling (although I'll admit they probably wouldn't race them). I completely agree with Joe's recommendation. Get a Brompton for the quickest, most compact folding configuration, a Friday for a good quick fold or a decent disassembled size, and the best riding characteristics, and a dahon for economy.