Selecting a new server (OVH)

Hi! I'm planning to buy|rent|lease a new server to replace the one I'm using now. The best option seems to be in OVH, a server with one 2x512G SSD and one 2x4TB softRAID arrays. What can I use the SSD drive for? It's too small to use it for the / partition (mainly because the /var directory grows too much). Is there a way I can use it as some kind of cache to make the server faster? Any Ideas?