So you've got a Galaxy S device and you want it improved. You'd like it not only to work better, but faster. Have you taken a bite of Voodoo? Once you do, you'll find that there's a Lagfix that'll replace your cruddy RFS filesystem with the Linux-standard Ext4 filesystem. What's that do? It restores your I/O performance and overall user experience to the speeds and quality it aught to be! Now, with the help of XDA member supercurio, you can have these Ext4 speed improvements with a totally safe mount option on /data! Hooray forever!
You can take a whole big look at this situation over at XDA forums, and NOTE: this functionality is already implemented in Voodoo, so if you're up on that, you're already a step ahead. See [this thread] and tell us how it works for you - we got a 15% speed increase on the I/O! Ohh baby.