In the past, I've mentioned problems I've had with the I/O limiter when trying to seed a torrent from my Linode. After making some major changes to my system (I'm now using Sarge instead of Woody), I've found a way to avoid running into problems with the limiter.
The key is to use a separate filesystem for seed storage, and format it as ext2 rather than ext3 (or any other journalled filesystem). The overhead from journalling seems to be the killer.
I've been on a torrent at bt.etree.org for a while now, and my I/O token level has mostly stayed near 400000 using the ext2 filesystem for the seed, even though I'm pushing out 500 kB/s.