Not all. Some sites, you have to sign up to play, some sites you just get cooler things if you sign up, and some you just don't have to sign up.
meez is one awesome website.
club penguin quick hit football power soccer
The pogo gaming site has some awesome, fun games and is free to sign up and play.
best playing games you can sign up to .com
Grow some balls.
you can sign up for free but the games aren't (some demos could be)
On some games a double coupon sign appears and click it to put your double star coupon in.
there are lot's of good sign up games! Kabillion poptropica Club penguin babydow virtual baby habbo hotel happy meal 3.0 Kidscom.com Wizard101 pandanda Hope this helps :) some sign up games are for supersecrets mostly for girls Some for boys ( i think ) weeworld and mostly for both Have fun ( it's fun for me ) pixie hollow Disney fairy zwinky cuties Garden party world Spark city whuddle world secret builders whyville
You can sign up for girlsgogames.com or club penguin!?
No sign up is necessary to play games, but you will need an account. Once you log in to the site you should be able to find several games to choose from.
you can sign up for addicting games,armor game, and y8 and y3 : ) and you can sign up for roblox