Not because they are funny - just someting about them that tickles your funnybone.
For example, I always got a chuckle over the drummer of Cheap Trick - Bun E. Carlos. First, there’s the slightly silly name - then the persona - deadpan expression, cigarette always dangling from mouth - black vest with button down shirt - just so NON rock star drummer. (Rick Nielsen also seemed funny, but more forced - like ‘Look at me!I’m being silly!’)
Any others?
Must be a drummer thing. The drummer for the Rolling Stones (whose name escapes my still sleep addled brain) has that effect on me. There he sits, drumming away with that smirk on his face that seems a little bored and condescending and just seems to say: “Yeah… can you believe people are still paying the big bucks to see an aging Jagger prance around? The man’s a spandex wearin’ chicken for gods’ sakes… idiot. We still get the chicks …young ones!.. Sh*t, even I can’t believe Richard’s is still alive…what a bunch of doofs…Where’s my drink?”
I love that guy! Cracks me up everytime.
Elton fucking John. That man. That hair. Those clothes. Maybe I wouldnt dislike him so much if he didnt spend more money in one week on CD’s than I will earn in my entire LIFE
O-Town.
I mean, come on.
Cervaise, YOU come on. You’re putting O-Town in the ROCK Category? 
POP stars are all about laughing it up.
Nobody’s laughing at Twisting F-ing Sister? All rough and tumble “we’re not gonna take it”, and yet we’re wearing blue eyeshadow and Cher -like Wigs??? Come on.
jarbaby
For some weird reason, I find Bono hysterical. I don’t know why–maybe it’s the name, or the odd stage personas, or how he really gets into songs when he sings them. Plus, he’s kinda my all purpose celebrity–whenever I just randomly need the name of a famous person. . . Bono!
The Cramps in general make me chuckle, as do The Pogues.
I’ve always gotten a kick out of Ted Nugent. He’s so goddam right-wing, pro-hunting, pro-gun, well-spoken, unapologetic, politically incorrect and he’s a ROCK STAR for chrissakes. God bless him!
Every time I see Curtis Mayfield in Superfly, I think of Jiminy Cricket.
Art Alexakis (sp?) of Everclear. They were decent once, but descended into lameness so long ago that it makes my eyes roll right out of my head to see him mugging and posturing in their vidoes as if he were STILL COOL. It’s like he has a little thought balloon above his head that reads, “Ah, the kids love me, I got 'em all fooled…”
Fred Durst. He tries so hard, it’s funny. Maybe the only thing more humorous is his rap-rock mook fans.
Metallica. I can deal with James Hetfield, but Kirk Hammett, I don’t know, he always seems like he’s trying so hard to be cool just like the big kids. “Look at me! I’m playing guitar for METALLICA!!! Couldn’t you just die!” He’s overly earnest.
And Lars Ulrich. The guy who had the problems with Napster? Every time I look at him I’m reminded of the MetalliCops cartoon from the Camp Chaos Napsterbad series. Lisping, crawling around the stage (and James) barefoot. “I’ve got such a chubby!”
His name is Charly Watts. I laugh at him too, but mostly because I think he passed away in 1983 and just doesn’t realise it yet. 
I’ll second Twisted Sisters Dean Snyder. Didn’t he file his front teeth in the shape of sharp teeth? I mean, really.
Lemmy Kilmister of Motorhead makes me laugh too. But then again, he really IS cool. And he’ll kick my ass if he spots me laughing.
To end the list: any metal group vocalist that uses words like “fuck” and “Satan” more than 5 times per show while addressing the audience.
I love AC/DC just because they wear the same clothes every time I see them on TV. Angus Young makes me giggle sometimes…what a stupid outfit! But I love them anyway.
Kid Rock. Need I say more?
Gwar is a damn funny band
My favorite on the good side of funny is Robyn Hitchcock. Seen him in concert several times and he really is a born comedian. “My Wife and My Dead Wife” is one of the all time funniest songs, in a creepy sense of course.
I was saved from the hair band explosion in seventh grade by Rikki Rocket of Poison. Something inside me told me I couldn’t possibly take someone seriously who spelled Rikki with two Ks.
Well, anyone who loves Spinal Tap knows how hilarious it is when a not-terribly-bright rock star takes himself seriously, and starts pontificating on important subjects, as if he has ANY qualifications for offering an opinion. It’s even funnier when they’re surrounded by sycophants who nod Marty DiBergi, as if awed by the wisdom he’s hearing.
Now, I’m as big a Beatles fan as anyone on this board, but… John Lennon was hilarious in both a positive AND a negative sense. When he was making smart alecky remarks and bad puns, when he was playing in the bathtub with his toy submarine, he was hysterically funny. But when he tried to offer deep thoughts on war, peace, God and the universe (while journalists hung on his every syllable), John Lennon was funnier than Nigel Tufnel or David St. Hubbins could ever be! But that’s what happens when people assume a blue-collar high school dropout MUST be an intellectual, just because he writes great songs!
What can ever be funnier than a perma-grin blonde hard rock lead singer wearing assless chaps and an oversized foam cowboy hat hopping around on stage straddling a giant inflatable microphone? Nothin’ I tells ya, and David Lee Roth invented that bit, you’ll never see your Dave Matthews or Backstreet whatevers coming up with something that is pure comedy genius like that.
If slapstick is not your thing, the members of Fugazi have a very dry sense of humor, and show genuine concern for their fan’s comfort and enjoyment at their shows. They played here in tiny Jackson, MS a few years ago, and Ian told a funny story about eating at a Chinese restaurant in town. He led the crowd in a chant of the place’s name, “Ding How! Ding How! Ding How!”. A classic moment, and I visit Ding How weekly in their honor.
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I still don’t understand why everyone has to hate on Kid Rock and Limp Bizkit. Whether you like it or not the Rap-Metal combination is the new wave of Rock music just like Alternative, Hair Bands, and Grunge.
KR and Limp Bizkit are the ones leading the charge. In 10 years when the new type of Rock music takes over, we will hear them on the radio and sing along, just like my parents do with The Beatles.
Now back to your regularly scheduled Music hatin’.
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More like Poison, or Vanilla Ice or something. Limp Bizkit’s already played out. Kid Rock had the one song and that was that. (However, I likes me some Korn. Yeah, I know. Go figure.)
As for rock stars that make me laugh, Rob Halford left Judas Priest and came out and tried to have a solo career and whatnot a few years back (we’re not at the funny part yet). I’ve never particularly cared one way or the other about Judas Priest, and think they probably should have thrown in the towel right there. Instead, they hired a new kid to sing lead vocals, and, get this, gave him the nickname “Ripper.” I say again, there is actually a formerly-respectable heavy metal band with a lead singer named “Ripper.” The mind boggles. I didn’t think it was possible, in this ironic age, to be that utterly uncool anymore, but there you have it.