If you’re running Windows, have more than 8GB of memory and a multi core CPU you can give SL a bit of a boost by placing the Cache into a ram drive. This can also extend the life of your hardware if your computer uses a SSD.
Just finished putting up a tutorial showing how to do this using the free persistent RAMDisk software from Dataram. There are a couple of caveats but on the whole it does seriously boost rezzing times in locations you have previously visited.
I plan to do something similar for Linux in the near future.