It’s not the most bad-ass robots, so that eliminates the need for Bender, Cameron, KITT, and Bishop to be on the list . 
What about CHEESE from Mac & Cheese!
I chose that stupid freakin’ owl from Clash of the Titans. Even as a child, I thought that thing was stupid. I’d hate to think what I’d think of it today.
Twiki was a serious contender for me, but I took pity because of his medical condition.
What about Hymie (I think that was his name) on Get Smart?. But you’re right all pale in comparison to Twiki.
The stupid owl was an obvious R2-D2 knockoff, but then so was Twki. Both annoying, but Twiki got my vote because of his stupid vocalizations.
Hey! You forgot the robot-dog from Battlestar Galctica! Dagget or some such rot.
R2D2 may have been cutesy, but he could also fix an X-wing’s mechanical problems in flight, hack the main computer of the Death Star, and kill people (I don’t think he was ever shown killing someone, but you know he could).
Twiki was useless. Couldn’t do a damned thing.
Hymie from Get Smart.
Muffit, the Daggit, in the original Battlestar Galactica.
Fi and Fum from The Lost Saucer.
Yo-Yo from Holmes & Yo-Yo.
Vicki from Small Wonder.
Kryten from Red Dwarf.
Hands down it’s Twiki!
[sub]This is a good reference, but don’t pick ones you don’t independently remember.[/sub]
What about the bear from A.I.?
Voted R2D2. He was so damn *smug *and pleased with itself all the time. Very irritating.
He’s also a goddamn min-maxer 
That’s what I came to post. It’s particularly galling because it’s what made me realize the series was going to be crap.
So many annoying robots, so little time.
How about Gort? smug bastard (Actually, he was pretty cool)
+1
Data, Bishop, and Cameron are far from sidekicks. They’re major characters. None of them are annoying, either (at least to me; i know some persons dislike Data).
I felt that way too, at the time, but the point of the movie wasn’t to be an accurate portrayal of Ancient Greek legend, it was the last gasp of stop motion animation in a major Hollywood film. So Bubbo’s twitching and whistling was sort of an an homage to the technique happening around them in each monster.
P.S. Bubbo is actually mythologically significant. Athena did have a mechanical owl, crafted for her by Hephaestus, that marveled the other gods by being obviously mechanical, yet obviously alive. Why this impressed beings that could create real life on their own was never well explained for me.
The other Olympians were amazed because Hephaestus had crafted an entity which lacked the divine spark, but yet was obviously alive. It would be as if I presented you with a seemingly-traditional newspaper that nevertheless had hyperlinks in its text, so you could touch a photograph and enlarge it, or go to another article about the photo’s subject. It’s nothing you can’t do on your laptop, but you’d still say, “Wait … that shouldn’t be possible on a sheet of paper.”
How about Fender(Robin Williams) from the animated Robots.
Sure the movie overall was crappy but did they really have to drag out Williams again to do his shtick?
It’s almost not worth it, since you will all hate me, but I choose a write-in candidate:
“Johnny-Five is alive!”
I cannot figure this sentence out, please ellucidate.
An homage to the mosters around them? How can you do an homage to something happening at the same time as you?
He was less annoying than the kid.
Your mother was a snow-blower!
Enjoy,
Steven