If you have a surplus in donations put it towards your next months server bill donating is a good thing but isnt always feasible.
We have a stash of games from the sale we can raffle away, I bought at least $30-40 of stuff for that exact purpose. Those plugins... I have mixed feelings about them... and I remember that valve wasn't too happy with them a while back. First they politely asked people to stop then they disabled some of the functionality necessary to use them and people had to find workarounds. Also don't forget FFN used to have custom trails and glows etc as donor perks until the plugin broke... and people didn't want those back when I asked about it. We already do... but there's just no easy way to show rollover on the progress bar.
How would people feel about donator slots on our servers as a supporter perk? Note that it wouldn't kick anyone for a donator, rather the server would have hidden slots above 24. If a supporter joins a full server, no new players will be able to join again until the playercount goes below the number of non-hidden spots.
Always wondered why we DIDN'T do that. As long as it doesn't kick people, it's completely fine in my book.