So this dude goes into a bar with a shiny new watch on his wrist.
He sits down next to an attractive woman, and glances obviously at his watch several times.
"Is your date running late?" she finally asks.
"No, I just got this high-tech watch, and I'm just testing it out" he replies.
She says "Oh really? What does it do that's so special?"
He tells her proudly "It's a telepathic watch. It knows all kinds of things going on around it, and it communicates those things to me telepathically."
"Wow!" she says. "What is it telling you now?"
Smiling, he says "Well, for example, right now it's telling me that you don't have any panties on."
To which she snickers and says "Well, I'm sorry to tell you this, but your watch must be broken, because I certainly do have panties on."
The man looks at his watch, taps it a few times, and says "Hmmm... it must be an hour fast."