Me Three Edit Meaning

1.

In a situation when one person says something, and another one agrees with them, he/she might say "Me too". If you also agree with them, but don't want to be seen as boring (by saying "Me too" just like that second person) or stupid (by saying "Me too too") you might want to say "Me three".

Three students during a lecture:

Wojtek: What I wouldn't give for a Playstation 3 right now!

Sebastian: Me too!

Adam: Me three!

See me too, yeah, ditto

2.

The lonesome person who says "Me Too!" after someone already says it and instead says "Me Three!" which doesn't really make any sense.

Bob: I want ice cream.

Jack: Me too!

Bill: Me three!

See me, two, too, sad, lonely, bob, jack, bill