Ah, we've had tons of these threads. I don't know why we don't make an official stickied one.
Here's everything I've got on my phone right now. Paid apps I've starred (*)
-WeatherEye: Canadian weather from The Weather Network.ca
-Facebook
-Units: Free unit converter, does currencies too.
-i.TV: TV and Movie guide. Crashes a lot though.
-NewsCanada: News reader
-AeroWeather: Aviation weather, I use this for accurate wind speeds when RC flying
-UrbanSpoon: Restaurant finder
-Dictionary!
-Shazam: play a song for it, it will tell you what it is and point to it in iTunes Store.
-Translator
-iTalk Lite: Voice recorder. Kind of superfluous now though.
-Remote: remote control iTunes and Apple TV
-Darts: A lame dart game I should get rid of
-Wikiamo: Wikipedia browser
-*Decibel: Sound Meter
-Lonely Plant Mandarin: Learn basic mandarin phrases with sound
-AIM: AOL Instant Messenger Lite (free) version
-SHOUTcast: Online radio
-iFighter Lite: 1943 style game
-Tap Tap & Tap Tap Revenge 2: Guitar Hero knockoffs
-Wolfenstine 3D*: Classic shooter
-Yellow Pages
-MotionX GPS Lite: GPS app has some added data such as elevation, etc.
-Air Mouse Pro*: Remote control any PC or Mac with keyboard and mouse function.
-Cheap Gas
-Google
-Skype: VOIP calling over Wifi
-Traffic!: Name says it all. Gives you traffic reports
-Scotia Finder: Finds the nearest ATM or bank I use. Available for other banks too.
-Flickr: Photo sharing
-BBC News Reader
-VNC: Remote screen sharing for Mac
-iGO Union Station Departures Board: Train/bus schedules for the Toronto area
-Big Day Lite: Basic countdown app
-RockBand*: It's RockBand. Wish it had better songs though.
-WordPress: Blog poster. Now if only Google would get one for Blogger!
-Fido My Account: Gives my account balance, minutes/data usage