The only time I can tolerate hacking in online games in when the hacker actually created the hack. In that case, I feel they have earned a little fun.
Script-kiddies are just cancer. Learn to make your own hacks or gtfo.
While I'll argue that the effort spent doesn't really validate ruining someone's fun,
I did also use the mentioned Rakion hacks I did just to mess around in the free for all DM mode. I didn't go around murdering everyone, and people were even wondering how fast I could throw bombs or shoot fireballs.
I also forgot to mention that I also cheated in S4 League. I changed the rewards around for the achievements, and edited a mission which made getting that achievement much easier. Basically spawning the max number of enemies that could spawn at a time without breaking anything, blow them all up in one shot across 4 waves, murder self, restart mission.
The difference between the way I did it and the way other people did it, they either spawned too few or too many enemies. Too few (advertised as the 'non-glitched' way) would make the process so slow. Too many would of course break the game. A major fps drop and over half the enemies not moving and not able to be killed. You would have to kill yourself on the first wave because it's impossible to proceed without killing everything, increasing loading times. The only reason I don't like including this one is because I used a tool that let you extract, edit, and repack files, and it kind of feels leechish.
I guess the gameguard bypass for B&S was also leeching but was worth sharing because of the reason for using it. The bypass itself was like... a 4 byte difference in a dll or something like that. But the guy who made it for me told me to not distribute it. I still posted it on WineHQ that the game does in fact work if you can bypass gameguard and then I got messages asking for it.