Freesound - The Freesound Project is a collaborative database of Creative Commons licensed sounds.
Sample Focus - The easiest way to find the perfect audio sample
Whyp - Free & fast audio sharing site
Moody sampler - A cloud connected audio sampler, including 1000+ instruments
Vocaroo - Vocaroo is a quick and easy way to share voice messages over the interwebs.
Userflows - Automatically generate user journeys