The 400WSM has been done and I think it is the coolest.

For the Ruger and a wsm case, its fine by me if its been done before! Thats just a whole lot of power, and it really can't be all that common. I think I'd still like the basic profile of the 458 Alpine though, with the blown out, low taper and sharp shoulder to maximize powder capacity.

I think using 50 beowulf reamer and dies using 375 ruger brass on a wsm donor is a brilliant idea. Limited mods to get to work and simple simple simple.

Interesting...please explain a little more, I'm not very familiar with the 50 Beowulf. Is it a .500 like the 500 S&W? If so, I thought that would be a cool idea as well. Thats a big damn bullet going pretty fast! I'm guessing it would be very similar to the .50 B&M....but what I don't get is how that guys headspacing with a straight walled case with no shoulder or belt??