I used to be 3:
DBM - Most raiding guilds require you to install it.
Recount - For my own personal use
RogueBars - Made my life a lot easier keeping track of certain timers.
When I came back I added a 4th:
Spell Flash - I used it to get back up to speed quicker. I hardly pay attention to it but it's still handy every now and then.
Now, if they could ever get Peggle back I will add that sucker in a heartbeat.