The SearchAndEditBundle from Paul Tuersley on AE Scripts puts 3 scripts together for the price of two: pt_EffectSearch, pt_ExpressEdit, & pt_TextEdit. These 3 scripts lets you search and edit Text, effects, and expressions throughout AE projects at once -- handy for complicated projects.
The much anticipated ExpressEdit is brand new. The 2 others are newly updated; EffectSearch now has the option to do effect instancing, which was a popular feature request. Here's Paul Tuersley on ExpressEdit: