Do you mean role-plays without need of a character sheet?

I've attempted RPs like that before on other sites and they tended to be on the chatty side of things. 

Here's a sample from 2010 of a RP I GMed [to some level] that lacked character sheets:

http://www.minecraftforum.net/topic/11150-rp-thread/

Note that I was a much different person when 13 and the quality is pretty shitty and the RP at times turned into straight up chat.

In 2011-2012 i've seen a person do it semi-successfully in the sense it lasted, but quality wise was a borderline incomprehensible mess. Higher quality than what I pulled off though. Still was a mess of mary sue brigades and really badly managed story flow [mostly the GM just threw a bunch of random things at the posters]. Did avoid turning into chat to some level though.

Sample:

http://www.minecraftforum.net/topic/548532-casual-multiverse-creation-always-accepting-forver-you-will-be-banned-if-you-are-not-serious/