Yes, lets finally talk about a Vista feature which is so never talked about. I am sure you have come across the word ReadyBoost or ReadyDisk. The only difference is just the media, one is a flash drive, the other is a damn fast HDD (like the raptor).
I wouldn't want to conduct a test again since there are tons out there. See these :
There are more, but I find this report realisitic. Now, my side of the story. A cheap Flashdrive 4GB at $30+. With my PC max to 3GB (4GB won't work in 32bits OS), is there anything else to boost performance? Yes, there is and its cheap. I got this un-certified for ReadyBoost stick and plug it in and guess what? It's fast enough for ReadyBoost. Since its cheap, I just put all the 4GB into ReadyBoost. the recommendation however is to match you memory. 3GB to 3GB of ReadyBoost, just similar to swap files.
Before I go on, I know some people will think this is cheaper than putting in 4GB of RAM. Well, that is correct as far as cheaper is concerned. But its not FASTER. ReadyBoost is more like putting the swap file onto flash disk. Flash disk have much much more performance and power in random seek compare to HDD. Moreover, for thoseo f you who does not have the technology to defrag your swap file, ReadyBoost will ready make the swap file look bad. Therefore you will have a significant boost in performance.
Now, for myself, bootup improved a bit, but not much. However opening and closing applications and games, well, that is the part that kick ass. And guess what I heard its not even properly optimized. After installing Vista SP1, you will kick asses a lot harder. :)
so, its really good (and cheap) to upgrade and push your day to day performance (yes, not talking about 3DMark or just to win in benchmark scenario). However, for the crazy and the zeolets, let me say this, the choice of your stick determines how much harder your kicking is (on the ass). By far, I had seen (with my own eyes) that fastest being Umbrella's (sorry, I mean Sony's) Micro Vault Turbo with Read/Write 26/19Mbps. Its a freaky $90 here for the 4GB, comparing to other cheaper ones such as the one I got for $32. Of course, for the zeolets, there is
OCZ's ATV Turbo USB 2.0 which is 35/30Mbps anytime (which I found cheapest USD$67).
Sony's Micro Vault Turbo 4G
OCZ's ATV Turbo USB 2.0
And last thing, if you are using Mac, TOO BAD. If you are using Linux, TOO BAD + Does USB even works for you?
Here is a list of user review ReadyBoost devices :