No one has mentioned the Saunders fixed-size easels (non-adjustable). While I also have a Saunders 4-blade, I find the non-adjustable easels faster to use. You can focus the square image from a 6x6 negative anywhere on the 8x10 or 11x14 sheet, the negative will give you "clean edges" by itself. (I have one in each of those sizes, which are the only sizes of printing paper that I use.)
As for contact sheets, like many who have already posted, all I do is put the negatives into transparent PrintFile sheets, put the negative page over a sheet of printing paper, and lay a pane of glass over the "sandwich" and print. Works fine, and you don't need foam under everything at all.
I'm also a fan of the Rotatrim cutters, if you mount and frame work, you will ultimately need a paper cutter, and Rotatrim is simply the best. Like easels, they last forever.