I installed http://www.superspeed.com/desktop/supercache.php for windows and the result is awesome.
Every program I run is faster.
Basically it uses the memory to cache data. Simple idea. I also use delay write.
Something like that in linux?
The Linux cache is a block cache not a file cache. In that respect Linux already has this feature as it's cache. It seems the only special thing about Supercache is it's a block cache and not a file cache.
From the Linux System Adminstrator's guide...
Linux uses write-back buffering which writes to the disk after the cache. This is the same as delay write.
So Linux already has every feature of Supercache.