Andrew Birkett's nobugs.org
Here’s some pictures from the first run of my aluminium-melting backyard furnace. You can read about building a simple furnace like this in the excellent Charcoal Foundry, part of the Build Your Own Metal Working Shop from Scrap series.
Basically, you need to line a bucket with a substance that’ll tolerate high temperatures without degrading. Then you light some charcoal in it, and by blowing air through you can achieve high enough temperatures to easily melt aluminium. By using this simple furnace, you can cast custom parts for motorcycles, fix household items .. whatever you like.