I seem to be able to make the "Search this forum" function crash at will when searching these words together:
data validation list
Remove the word "list" and it works.

It opens a new page with the follwoing error:
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 524288 bytes) in /home/eforum/public_html/search.php on line 1156
Seems I can do this in any of our forums so far.