Dropbox, free 2 GB account, store your music, photos and video in the cloud and stream or download directly to your Iphone. Very cool.
Evernote: Again, cloud storage for your notes and photos, with geotagging for both your notes and photos. If you travel very cool way to chronicle your path.
Also, free OCR for photos and docs you upload making them either tag or keyword searchable. Free account
ReQall: Free memory jogging/location based app. If you're like me and have a thousand things going on, very handy.
