Due to Jon Anderson's discouragingly high vocals, Yes has often been described as the most annoying band in the world. This did not prevent them from making music - and lots of it.
Definitely not the most accessible band in the world, Yes tackles what appears to be inane subject matter and takes it to new heights, or depths. For example, their Tales from Topographic Oceans is a double album based on the Autobiography of a Yogi. I can't think of any book more boring, except perhaps something written by the Dalai Lama.
The Autobiography of a Yogi by Paramahansa Yogananda. No drugs, no sex, no rock 'n roll. Chaste people remove themselves from the breeding populace. By the principles of universal Darwinism, we should thank them for the favour.
Yes is perhaps equally famous for featuring the art work of Roger Dean on their covers.
Yes, we Can, apparently. Can is one of those bands that change their tune with each album. Relying heavily on instant compositions (or improvisation), the music is surprisingly coherent. Especially considering that the band is very multi-cultural and probably stoned out of their brackets. The influence of jazz and Karlheinz Stockhausen is apparent. Less apparent is how dangerous it is mixing jazz and Stockhausen.
Notable albums include Ege Bamyasi and Tago Mago.
Gong is known for their two most famous strands, namely the hippie commune psychobabble of Daevid Allen and the caffeine-themed jazz of Pierre Moerlen. Don't worry, it's all good.
Daevid Allen. "Nobody knows I'm lesbian".
Of course no nerd band list would be complete without a guitar hero or two. Gong features Allan Holdsworth during their marimba and caffeine stage, on such albums as Gazeuse! and Expresso II.
The Ozric Tentacles relies on space rock to infect the minds of their unsuspecting audience. Since they've never had major label support and yet managed to sell over a million records, they must be doing something right. Their music is instrumental, which is a bit of a relief after listening to Yes.
Emerson, Lake and Palmer
Emerson, Lake and Palmer is conspicuous because they are frequently noted on heaviest bands of all time lists even though they do not have a guitarist.
Comprising of insane drumming and some of the wildest keyboards you're ever likely to hear, they frequently cover classical repertoire in their, well, repertoire. Some muzak hits of theirs include Mussorgsky's Pictures at an Exhibition and Copland's Fanfare for the Common Man.
The cover of ELP's Brain Salad Surgery. This is artwork by H.R. Giger. The original featured a massive schlong that had to be airbrushed out to please the censors.
But rest assured, the band is really loud despite classical pretentiousness. Keith Emerson's party trick is playing keyboard with daggers. I'm not sure if he's tried it blindfolded on a wheel of fortune but he should look into that.
I couldn't find any bands who sing in Lojban. Sorry.