If you really want some tough steel, get a NASCAR axle from Paul Garrett up at the Folk School. It is pretty amazing stuff. Best of all it doesn't need any kind of heat treat just let it air cool. I've got a couple of chisels made from it. I also made a pair of tongs from it. We'll have to see what happens the first time they get quenched when hot from holding something. I don't think that will be a problem though because while tongs get too hot to handle, unless you're not paying attention they should never get any color.
Also when you cut it use an abrasive wheel. If you try any kind of saw, the steel wins. Another thing I learned about the axle steel is that you have to work it hot. Once it loses most of its color it gets very hard to move and you can crack smaller sections like tong bosses. Wonder how I know that one!