• Exposing software application events via Twitter, so i can 'follow' the critical systems events. My initial thought was to start with Windows Event logs exposed via Twitter (with some filtering, obviously); that's the low hanging fruit. The next thought was ensuring that Windows Event logs (or whatever) were populated by conext-sensitive monitoring software hooked into apps to provide business-level notifications, which would then be picked up by Twitter and 'followed' by interested parties ("Hey, your db cluster just missed a heartbeat", or, "You're close to breaking your processing SLAs, maybe check on what's up?")
• Making Twitter reach across firewalls and into business apps. I'd like to submit my project time entries via Twitter. I'd like to post updates to my internal project blog via Twitter. I'd like to... fill in the blank. IOW, have the apps follow my "tweets", pick out the ones intended for them, and do something intelligent on my behalf.

that doesn't seem that outlandish, right? so far, the use of Twitter as a public IM system or another vehicle for messaging and spam underwhelms me.