WowAce

Shows the spec of people around you in the tooltip.

Add-on that shows in a unit tooltip window a number of killed mobs of the same kind

"Your quest log is full". How many quests do you have in your log?

Item link modification

Creates a broker plugin for all your broker launchers

Shows loot information in item tooltips

Never forget which one in that 5-mob pull casts what spell again.

Watch tooltip updates to announce when you find specific objects

Shift-clicking on a user name in chat shows a tooltip with their whois information.

Really very early stage. No, earlier than that.

Calculates the relative value of attributes towards physical dps.

Tools to easily compare gear among party members.

Shows the Guild Achievements Points and Members in the tooltip

Adds an icon to item, spell, and achievement links

Adds tooltip for debuffs (and other things? you found out: no).

Enables RatingBuster to calculate selected buff effects even if you don't really have them

Very very simple tooltip

Shows what stat was reforged in item tooltips.

Pre-Alpha of SpiderEyes power desplay. Do not distribute!!

Tooltip text modiffier based on DogTag.