Pimp your UI - Best Unit Frame AddOns
One of the first things any player should do is modify the default Blizzard Unit Frames (player, target, tot, focus, pet, raid, etc). There are many great things about the Blizzard interface, but their unit frames are not a highlight. The most recent 4.0.1 patch has issued some improvements, but they still do not compete with the third-party addons available.
Some options to get you started from basic to more complex:
SimpleUnitFrames - SimpleUnitFrames is an extension to the default WoW Unit Frames. Rather than a complete unitframe replacement, this addon adds further information and features to the existing frames and allows a greater degree of customization to enhance their usability.
SnowfallUnit - This addon is a unit frame modification (player, target, focus, party, arena, raid, and so forth). The purpose of the addon is to add critical missing functionality to the Blizzard unit frames and improve their readability. The addon modifies the Blizzard unit frames without totally replacing them.
ag_UnitFrames - This addon is a full unit frame replacement. The most basic of them all, but offers a fair amount of configuration.
Shadowed UnitFrames - Highly configurable unit frame replacement. All configuration can be done on multiple units at once through the global configuration, so if you want to change the height on player/target/party only, then set height for tot/totot/focus/focustarget you can do that easily. For the people who have to tweak every single option, you can enable advanced configuration which will show extra options. But, you do not need to do this by default, it’s only for people who really want to tweak every single thing.
Stuf - Stuf is a replacement to StellarUF. Stuf has the same default layout and feel of StellarUF, but Stuf is highly customizable. The author has created a simple to configure unitframe addon that can handle the most complex needs. Recommended
XPerl - A much enchanced version of Nymbia’s Perl UnitFrames, and a complete replacement for Blizzard’s default unit frames, including raid frames and raid tools, with many additions and improvements over the original Nymbia code.
PitBull4 - PitBull is a Unit Frames addon that provides maximal customization and undergoes rigorous efficiency testing. It is created in a modular framework, which allows for mulitple authors to put their skills to work creating this great project. It has support for many different kinds of units: player, target, pet, pet’s target, target of target, target of target of target, focus, focus’ target, party, party pets, party targets, party pet targets, raid, raid pets, raid targets, main tanks, main tank targets, main assists, main assist targets, etc. Recommended
oUF - Minimalistic frames that are very low memory. They will work fine if you install them but they have no in game setup. All changes need to be done in the Lua code including their location on the screen. To use this mod you will also need to download and install a layout. Advanced users only - configuration in LUA only.
* source: vranx.com
** not all of the above addons are 4.0.1 compatible yet