Is there a way to customize vibrate patterns? Like many people my phone is most of the time in silent/vibrate mode. I was wondering if there's a way to assign different vibration patterns for different notifications, just like we do for ringtones and alerts with sounds.
Maybe there's an app that allows us to do that? I couldn't find anything yet.
SMS Popup does vibration patterns on a per contact basis (or for all texts).  

Handcent does it only for all texts.

Missed Call will do vibration patterns for SMS (per contact), phone calls (per contact),  Battery, Calendar events, device storage, etc.