What the World needs is a good 5c cigar

OK. That sounds a lot Off Topic, but it's a good interest getter.

What 3D Printboard needs is a table of G, M and F codes that are useful when calibrating our printers.

Here's some things I'd like to have the codes for:

1. Moving in the X, Y and/or Z directions singly or in combination.
2. What is the current steps/unit of movement of my steppers?
3. What is the code to extrude "m" millimetres of filament?
4. What is the code to make my extruder work without having to heat it? (???? Will it extrude 3mm filament through a 0.4 hole if it's not molten?)
5. What is my default steps/unit of movement of my steppers.
6. How do I update a value eg steps/100mm of extrusion?

These are a few I can think of off the top of my head. (Probably could find more if I engaged my brain as well)

Old Man Emu

Google and "gcode reference" gets you the Reprap one and lots of others.

Don't get carried away with the LinuxCNC Gcode, that's a real Gcode set not like these toy printers. :)