Adobe Audition

Someone should do a write up here. It's a perfectly fine audio editor with some pretty good frequency based noise removal (noise print). 

Plugins

RX 7 PRO (now RX8) - Very good at removing elements of a track. Can be used to make acapellas or instrumentals. Some tracks perform better than others. Can also be used to reduce background noise.

InstantDialogueCleaner _ Does exactly what it says to varying degrees of success.