I have this server setup: http://www.server4you.com/root-server/server-details.php?products=5
That gives an extra 60 GB OCZ Vertex 2 SSD hard-disk. I don't want to use it as storage. What should i do with it? Can i use it like extra ram or something for mySQL cache? What's your opinion?
You have the right idea with regard to databases.
Flashcache, maybe?
See: http://www.mysqlperformanceblog.com/2010/05/10/flashcache-first-experiments/
Is this the 2VTXE60G model or the 2VTX60G? if the latter, cheaper, part I'd forget about using it as a server part. The E-models have 28% of overcommit memory, the non-E model only 7% - this means that you have only a quarter of the additional memory set aside on the SSD to handle memory cell failures. Used as a cache or any other application where writes are common will see these cells fail at a rate beyond its design (35GB/day btw), once this 7% is used up it'll start eating silently into the basic 60GB until you have file system corruptions and data loss. Obviously going for the E-model puts this day off by a factor of 4, whereas enterprise-class SSD are over many times more again.
Think long and hard about using SSDs in routine-write scenarios, they're wonderful things when it comes to reads but their behaviour is not that of simply a faster regular disk, I'd hate for you to lose data and service by assuming they are.
I'd use it in a laptop/desktop myself, it's what it was designed for.