Like any other operating system Vista performs pretty nicely if you've got enough RAM, but sometimes you're just on the edge. Sometimes not enough, but not often enough to justify going from 1GB to 2GB or beyond.
So, apart from the smart stuff like stopping services you don't need and making sure you're machine is tuned up is there anything you can do?
If you have a high performance flash memory device (USB Memory Key, SD Card etc) then the answer is yes.... and it's called ReadyBoost.
Setting up a ReadyBoost device is simple (just follow the instructions here) and it's pretty much a set and forget process with Vista taking advantage of the extra memory to avoid paging to the much slower hard disc.
Of course once you've got ReadyBoost helping out it's nice to know how much help it's providing. If you're happy to dig into the vast array of performance monitors that Vista provides then check out these instructions but, if like me, you like your information pretty, simple and bite sized then check out this sidebar gadget to give you the information.
Of course running lots of performance monitors or an extra service and the sidebar itself to monitor the benefit may well defeat the benefit - thought that's starting to get into Schrödinger's cat territory!
I now leave a USB Memory Key stuck into my docking station for my Laptop. Most of the time when I'm on the road I don't need the boost (though the larger USB key I carry with me can double for that) but when I'm desk bound it's nice to take advantage of the extra USB ports and a smaller (2GB as opposed to 8GB) ReadyBoost certified device.