Brackelope, Denasi and Challonge seem to be the popular software for running tournaments. Which do you like? Multiple votes allowed. If you vote other, please identify the software in a post.
Is there anything else out there for other tournament formats, such as PAPA World Championship and European Open qualifying? In these you can pick say 5 machines out of a lineup of 10 or 20 and post 5 scores which are ranked against players' scores on that machine. You can enter as many times as you like, on different 5 machines if you choose, but each entry is a complete score in its own right. That is, your score is not your best performance on each machine for the tournament, but rather your best scoring entry.
Are there any other software for different formats that pinsiders recommend?