I agree, Event Notifications work for Deadlocks and so much more. Here's my blog posting on how I created a "generic" event notification service for all of my SQL servers. It alerts on database creation and drops, login creations, role changes, etc.

http://www.the-fays.net/blog/?p=239

No trace flags, no agent jobs, no temp tables, no WMI calls. I'd recommend that anyone reading it, take strong consideration to the updates about using certificates rather than changing the TRUSTWORTHY setting on the database used.