In forums, many people have sigs, such as a plain KevZho or ADK to ranging to (this is mine):

<ô_ô>

"Did YOU fail?" ~~Unkwon

"It doesn't matter whether you miss by an inch or a mile, what matters is that you failed." - Brian Gu

"When life gives you lemons, throw them back and demand limes." - Fall of the Conqueror

"When life gives you lemons, make grape juice and let life figure our how you did it." - Steven Hsieh

"When in Rome, act as the tourist you are, not as a Roman. You are not a Roman." - Brian Gu

"(Blub blub)" - Sammy the fish

"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." - Albert Einstein

"Families is where our nation finds hope, where wings take dream." - Former President George Bush

"A three-horned unicorn killed me to death, but luckily I survived. Then a hen pecked my head to a nub." - Jeffrey Li

"I am free of all prejudices. I hate everyone equally." - W.C. Fields

oooO
(      )
\   (
 \_ )                                                   
                        Oooo
                        (      )
                          )   /
                         ( _/
                                                               

   __     __     _                                  
   / _ \    |   \  |  |  D D D                 
  / /_\ \   |  |\ \|  |  D      D                    
 /_/  \_\  |_|  \__|  D D D    o o o

WHEN FISHIES INVADE...

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Do you think these sigs are a good idea?

They take up a TON of space...

Like KevZho said, a simple one would be just posting your username after each post.

ADK

yep.