mynoise.net It's got a huge list of generators for all sorta of sounds, from soundscape and environmental noise like coffee shops, to musical instruments, to white/grey/pink noise, and all sort of other things.

There's nothing better for when my tinitis is acting up and I want to play some tonal drones, or I just want to get into a mood by mixing some Tibetan singing bowls and a rainforest, or maybe just play noise-blockers to help me focus.