Spammer registration block?

[jamyam]

Hello there,

Recently there have been registrations on my forums, probably one or two a day, with usernames like 24afsdafx3 or f24fasdc8 and so on. Is there any way to stop these? I searched the forums to see if there are any scripts or hacks to stop it but I couldn't find any that were visible. If there is one, can someone point me to it?

I guess using that image verification thingy might stop it, but I hate those things...are there any other ways?

Thanks!