Marquee (streams messages across the screen) iHandyCarpenter (the BEST level out there, used it to build some shelves, looks amazing) iSteam (very well done steamy window effect if your into that sort of thing)
I personally find Midomi to be a far superior app - Shazam does not allow for humming, whistling etc... You can only find music by sampling the actual song or at least that is all it could do the last time I checked it out.