One of my older brothers (let's call him "Jim" so the title works) gets a lot of joy out of messing with people. He's not as fond of pranks as some of my other brothers are, so he just enjoys the smaller things.
When our grandmother was sick, people would ask how she was doing. And he'd make a serious face and say, "Well, she's in a better place now. She moved to Florida." But he'd always be sure to take a sip of his drink or cough for a moment between the two sentences. That way people thought for a couple of seconds that she'd died. Pretty mean, but pretty clever.
He also likes to plant little seeds of doubt in people's minds. He'll throw something into a conversation and never let anyone know he was joking. For example, I once heard him say, "Well, I was talking to my parole officer... um, I mean... a friend of mine who's a parole officer and he agreed with me." And then he didn't acknowledge that he'd said anything strange. So then the person he was talking to tried to figure out in their head whether or not he was kidding. ("He doesn't seem like a drug dealer, but maybe he was busted for possession. I could definitely seem him being a recovering addict ex-con.")
The funniest one that he pulled was convincing his girlfriend that he was a skilled accordion player. He actually talked to everyone in the family ahead of time and made sure that they didn't call him out on it. And then he came up with an elaborate story about how our parents had made him play when he was a kid. Even though I knew the truth, it was hard not to believe him. He's really convincing. But his girlfriend got pretty mad when she found out we were all in on it. She's kinda sensitive about being gullible. (She got excited when I told her that she should get the new "Accordion Hero" video game for him.) Plus, I think she might be a closet polka fan, and it hurt her feelings that we were treating it so lightly.