It's pretty stressful, but there is a way to stop him, I believe.
Every new member that registers, just check their I.P., and if it matches any I.P. that IceMan has used, just immediately ban that user if they don't have a really good excuse as to why.
Time consuming, thus impractical. The forum is not constantly moderated (even if we do come very close). That, and we do get quite a few new members every day. To verify each new account would be a little... Inefficient.
well, hampa could create a new script that checks the IP's of every member automatically and if it detects an I.P. that been used by IceMan or any of his other accounts, it automatically bans that user.