Some forum members have managed to incorporate the forum names into their vanity addresses. Here’s a couple I found .

Otoh
Profile https://bitcointalk.org/index.php?action=profile;u=20300
Address 1otohotohMoQoxHuxLBveQiZcV3Pji3Tc

DobZombie
Profile https://bitcointalk.org/index.php?action=profile;u=61730
Address 1DobZomBiE2gngvy6zDFKY5b76yvDbqRra

Story is - I guess they want a cool address with their name in it