Are there any good free sudoku makers?

I specifically want a program that I can solve the puzzles on screen with, and also print it out when I have to go or when I just want a pencil puzzle. I want something that can make a variety of puzzles. I want something COMPLETELY FREE OF CHARGE, not some stupid trial program. It would also be appreciated if it could make super challenger puzzles like you see in the puzzle books- you know, the kind that have 16 x 16 squares instead of 9 x 9 squares, as well as the "diagonal rule" (sudoku book purchasers should know what I'm talking about), where none of the numbers can be the same diagonally. Please help me here!