Which threads has visited a member?

[BirdOPrey5]

It wouldn't be too hard to make but it would take up tremendous storage in the database. The size of this table would approach the number of members X number of threads. On a 100,000 thread board with 10,000 members that could mean 10 BILLION records- 99% of servers can't handle that.

There would be other ways to store it but they all run into the issue of massive amounts of data on active forums.