Another to add to the list is Shaw cable services. There's been evidence both in this forum as well as other p2p forums of capping speeds for p2p use, eg: Even caps on other p2p programs. One day you get 100-150 KB/s & the next about 3 - 5 KB/s.
Example 2: Slow everywhere, Example 3: Lots of people using p2p,
Example 4: Bingo: Confirmation of Filtering at Shaw, Example 5: Bearshare Forums
(There's been word Vista III media is also related in its type of business practices.)