Adding to the multiple ways to switch spaces: here's a way to do it with just Blacktree's Quicksilver, without running any (other) third party apps.
In the Spaces control panel, set control-number keys to switch directly to a space.
Add a Quicksilver trigger, with this text (type dot and then this text): tell application "System Events" to keystroke (ASCII character 49) using control down
Set the action as "Run as AppleScript"
Set the trigger to use a keypress, then (you might have to hit the (i) icon to get the sidebar to pop out) set it to F1, and make sure you set it to activate on release.
F1 should now jump to space 1.
Do the same for F2, but with ASCII 50, and so on. You're just telling it to hit the control-n when you hit the function ...