RootBSD [1] has been around for quite a while. I personally use fileMEDIA [2] and LunaNode. fileMEDIA provides a set of isos, among which you can find FreeBSD, OpenBSD and DragonflyBSD (i personally requested them the DFBSD one). On LunaNode you can upload any ISO image or qcow2 file you'd like.

1: http://www.rootbsd.net 2: http://www.filemedia.de 3: http://www.lunanode.com