Fancy up the default AddOn List! Inspired by ACP by sylvanaar and it predecessors.

BetterAddonList has the following enhancements:

Search!
Move the panel.
Create sets that allow you to quickly enable or disable groups of addons. Including multiple sets in one allows you to create base sets of addons for enabling across multiple characters.
Shift-click the check box to "protect" an addon, preventing it from getting disabled.
Enabled addons with missing or disabled dependencies are shown in red.
Load AddOn button is always shown for unloaded load on demand addons.
See how much memory enabled addons are using.

Slash Commands

/addons - show the addon list, /bal and /acp can also be used
/addons load [set] - enable only the addons in a set, other addons are disabled
/addons enable [set] - enable addons in a set
/addons disable [set] - disable addons in a set
/addons save [set] - save all enabled addons to a set
/addons delete [set] - delete a set
/addons disableall - disable all addons
/addons reset - Reset addons to what was enabled at login

Protected addons will never be disabled.