I’ve been looking and trying out at least 7 different search&replace programs until I found PowerGrep for Windows.
It is totally awesome, FAST and easy to use. Another program, Actual Search & Replace worked through my folder with ~250 files for at least 2 hours, and this baby is doing in less than 2 minutes! There’s tons of options such as preview your searches first and saving backup copies of your files. RegExp support is also excellent!
A runner up would be good old Search&Replace from Funduc software but it is limited to one line of code – good for small tasks.