Basically, A poor mans SSD can be made using a cheap CF2IDE adapter -- these sort of things http://www.sintech.cn/en/index.html & http://www.addonics.com/products/flash_memory_reader/default.asp#int.
As CF uses an IDE interface, I understand that the CF2IDE adapters are little more than physical connects, so they shouldn't impact on performance. In other words performance of a CF-based pseudo-SSD should relate to it's speed rating. Also, it may be that NAND latency is the limiting factor rather than SATA vs PATA.
In terms of a boot system a dual CF2IDE adapter would be even better -- you could use a slightly slower (say 133x) 12-16GB card for the OS and apps, and a faster (say 266x) 4-8GB card for the swap/page file. The thing I like about the double CF2IDE adaptor is the possibility of having swap on a smaller/cheaper card, so NAND wear out of the swap can be contained to a more affordably replaced item (even with the wear levelling features in the memory controllers of the newer CF cards, I'd imagine the swap file would still present a problem).
Addonics promote/sell this for laptops, but I've yet to see any performance figures.