Thought you guys might be interested in this.
Bcache - BcacheWiki
I think this is a really interesting concept, unfortunately I haven't had a chance to try it out myself but I will do it as soon as I can.
Bcache is a Linux kernel block layer cache. It allows one or more fast disk drives such as flash-based solid state drives (SSDs) to act as a cache for one or more slower hard disk drives.
Hard drives are cheap and big, SSDs are fast but small and expensive. Wouldn't it be nice if you could transparently get the advantages of both? With Bcache, you can have your cake and eat it too.
Bcache - BcacheWiki
I think this is a really interesting concept, unfortunately I haven't had a chance to try it out myself but I will do it as soon as I can.