Yes. It's called caching.
Superfetch is Microsoft's version of the RDF in Mac Products.
I believe the OP wants to know if OS X replicates the recently/most used application precaching SuperFetch does.
I know this thread is way old but is there a way to do the whole ReadyBoost thing on mac? (use usb flashdrives as extra RAM)
i just meant a way to temporarily increase RAM without actually adding sticks of RAM