*sigh* if you're going to sign up for a new account pretending to be someone new to the community, it helps not to mention a comment from the end of an obscure thread pretty much only a handful of people would have read. </freeadvice>
The tools are not as complicated and specific as SuperFetch (afaik the api's needed to write a superfetch open source version is missing).
If the APIs were missing, how would SuperFetch work? It's entirely possible to write a replacement for it, although the phrase "reinventing the wheel" would seem to apply.
They use block based caching of all the requested data from the hard drive. So the access time would be sped up no matter what data the programs regularly used not just the launch speed.
As does SuperFetch, it's all about what it decides to pre-fetch that makes it apply to launch times rather than anything else.
I was testing ramdisk a few days ago and it got me thinking. The speed up was huge. Using a caching solution might be good both for performance and the longevity of the hard drive.
You're trading performance in one area (disk caching) for another (absolutely everything else that requires RAM). It might appear faster in isolated benchmarks or over short periods of time, but under real world usage ramdisk type approaches sacrifice far more performance than they gain.