Definitely barcode scanner. You'll see tons of sites (I like androlib.com) which showcase android apps and to download the app you can just scan the QR code. I tried appbrain but had a lot of issues with force quitting and connection errors. Sounds like a lot of people don't have those problems though so you may as well try it out. Most of the google apps are just toys at this point IMO (goggles, skymap, etc) but are fun for a few minutes. If you have a google voice account then the app for it is great. It integrates into your phone so well and you can set the dialer to make calls with it by default or to ask you when you make a call. I love it. I use flixster a lot, the engadget app, dropbox, NewsRob (google reader app, comparable to netnewswire on iPhone), FMyLife Official, TFLN, Layar is a cool one (augmented reality app), Paper Toss is a fun kill a few minutes type game, I love Abduction! if you want a DoodleJump type game (plus there's a free version), TMZ, oh, and last but not least, TicketTalker 3000 (the app from the 76 commercials).