My opinion is also that defragging RAM is useless. The only useful purpose to doing it as far as my understanding goes is freeing RAM currently be consumed by memory leaks from some poorly coded program. Also from what I understand is that RAM defraggers simply just reallocate all possible RAM to themselves and then deallocate it properly as all programs should. Any RAM that was being used by memory leaks is flushed to the pagefile since it is actually not being used, but won't be referenced again anyway, and all that is left in your RAM is what is actually being used.
However, RAM is volatile anyway so the best defragger is just a simple system reboot I think. Ofcourse a server requiring 24/7 uptime could benefit from RAM defragging I guess. I have no experience with such. For pesonal computers though, just reboot I'd say.
EDIT: My bad, you chose the best answer as I was typing all that bull$hit above lol.