I went to the lawn mower store and purchased a 1 quart gas tank that originally went to a snowblower or something. I connected a shutoff valve and some fuel hose to it to make an auxillary fuel tank for working on the bikes. It cost about $15, total.
If I have to remove the bike's tank, I'll hang the aux. tank on the handlebar so that I can run the bike when needed without having to replace the main tank. This works great when diagnosing problems or working on the fuel system because you can turn the gas on or off at will and you still have access to the entire engine. Your main tank can now be put somewhere where it won't get dinged or banged up. If you put the shutoff near the end of the aux tank's hose, it can save alot of headache and spilled gas when you have to connect/reconnect the fuel supply repeatedly.
This setup is fantasic when syncing carbs.