Amazon Cloud Drive and Amazon Cloud Player
If you want a free service to stream your music from your home computer to your work computer/android/iOS device, check out my service: http://www.audiogalaxy.comSince we don't store the music in the cloud, we don't have any size limits (the current winner has about 530,000 files).  Obviously this only works if you leave your home computer on, but we've found that isn't a problem for most folks.