i normally buss all my drum tracks to a compressor and use it to varying degrees...it can give great energy to the sound...however using too much can also just make it sound flat and pish (generally the case with all over use of compression.) another fav trick for a big snare sound is stick the snare in an aux send...apply reverb first then compress said reverb for a big snare sound. back to vocals...i record alot of my vocals in my specially padded out wardrobe for maximum deadness, then use the wonderful emagic space designer reverb in the mix. also a wee touch of overdrive can work wonders for getting them to cut.