A while ago Intel unveiled its Turbo Memory project which uses flash memory to boost the performance of your system. So far this technology is only available for notebooks but the chip giant is also working on a desktop variant.
This product is codenamed Cariboo River and it will slide into one of your PCI Express x1 slots, according to intel obtained by FUD Zilla.
Considering how small of a performance advantage you get with Turbo Memory if you have more than 1GB of system memory, it might still not be a huge hit.
The other problem is that it seems to require the use if Intel's ICH9R, which is more expensive than the plain vanilla version.
If it wasn't for the fact that Intel's Turbo Memory modules were so expensive, they might have been more popular, but as it is, it's cheaper to buy some extra RAM.