Two Pensioners (15)
An old lady and an old man are sitting in their retirement home.
The man turns to the woman and says,"I bet you can't tell how old I am."
She then unzips his fly, feels around for a while and finally says, "You're 83."
"That's amazing!" the man exclaims. "How did you know that?" he asks.
She replies, "You told me yesterday."
Joke found at http://www.geocities.com/Eureka/2531/n99.htm