as I understand it, you can do it w/ a regular mig, but be careful of getting a birdnest in the hose if you kink it. also, the shorter the line the better. A spool gun is better, because it draws the aluminum wire down the tube, instead of trying to push it.
If you have a mig, and some scrap aluminum, try it out- a 1 lb spool is less than $20.
also- I have not tried it, although I heard it can get brittle, but heres some sticks you use a torch/ braze--
durafix.com
I watched the vid- looks good from my house.
