g: Grabber, also known as Translation
r: Rotation. Hold down ctrl to rotate by 5 degrees each
s: Scale/Size (and Flip, but that's advanced stuff)
MiddleMouse+ctrl: zoom in or out (up is in, down is out)
MiddleMouse+shift: pan around
MiddleMouse: “Trackball style rotation”—rotate your view
f1/f2: Load/Save
f12: Render
f11: toggle the display of the render window
ctrl-x: reset to defaults (this loads $HOME/.B.blend)
ctrl-u: save user defaults to $HOME/.B.blend, which Blender reads at startup or when you use ctrl-x
tab: edit mode toggle, for almost any place