Converting sander/polisher to grinder

Darwins Child

I'd like to open up this thread to a discussion of the tasks that can be accomplished with a good grinder / cutter. I need some additional incentive to buy one.

For example, I have recently "machined" some custom-design jacking blocks for the Z using 2 x 2 aluminum bar and doing the "machining" with a manual hacksaw, a really good file and lots of blood, sweat, but no tears. How much of the work that is typically done with a hack saw can be done with a grinder? Specifically, could a sober you cut a fairly accurate 1/2" wide x 1/2" deep slot in a block of aluminum and, if so, how?

What imaginative things have you done with your grinder and what have you learned, good and bad, by your experience?

Do any of you have variable-speed grinders and, if so, what do you think of it and what advantages does it have over a fixed-speed unit? In particular, what do you think of the Makita variable speed grinders?

Thanks for any comments about your grinder ownership.