awinedrowning: if you are blind and you take LSD... does anything happen?
my initial answer to this is you probably feel an extraordinary amount of different things, not just things you can SEE as we have come to know what SEEing is.
the blind SEE with their skin, their ears. their mouths, their noses. think of a pentagon equally divided into five sections, each shaded in a certain amount. remove one section, leaving four sections, but still distribute the area equally, this time between four sections instead of five. this is how i always understood the way that those with sensory disabilities adapt. i could be wrong.
my initial answer would be to say that they'll probably start to continue with the standard effects of LSD (hyperactive, lucid imagination) that plays itself out in the standard sorts of ways. new ideas, new experiences, free from the boundaries we're used to, and almost haunted in each new idea's life.
my initial answer would most likely continue through to say that they would probably feel things that weren't real on their skin, they'd hear things that weren't real in their ears. although with their other senses, they might smell or taste things that weren't real as well.
the initial answer changes a little bit when you throw the idea of someone who wasn't blind their entire life. which then gets more fine tuned when you think about how much of their life was spent with vision, and at what accuracy. did they lose their sight by way of degeneration, or an instant act?
i read up on the drug, though, when i got home tonight. apparently, albert hofmann, the father of LSD, experienced "fantastic pictures, extraordinary shapes with intense, kaleidoscopic play of colors" when he closed his eyes on one of the first days of accidentally stumbling upon the more 'psychedelic' uses of this drug. three days later, he went on a full-on TRIP, taking a theoretic "maximum dosage", and ended up experiencing a maelstrom of things, as you can imagine.
he began to speak unintelligibly, and on his assisted bike ride home felt that he was completely stationary while in reality he was actually moving at a "very rapid" pace. for several hours, he thought he was possessed, his neighbor was a witch, and that his furniture was threatening him. one key thing he mentioned (in specific reference to the blind) is every acoustic perception, such as the sound of a passing automobile, was transformed into optical perceptions. the next day, he mentions, though, (in contrast to the blindness) that his breakfast tasted unusually delicious, and all of his senses were "vibrating in a condition of highest sensitivity, which then persisted for the entire day".
to further color coordinate:
...an experience of radiant colors, objects and surfaces appearing to ripple or "breathe," colored patterns behind the eyes, a sense of time distorting (time seems to be stretching, repeating itself, changing speed or stopping), crawling geometric patterns overlaying walls and other objects, morphing objects, a sense that one's thoughts are spiraling into themselves, loss of a sense of identity or the ego (known as "ego death"), and powerful, and sometimes brutal, psycho-physical reactions interpreted by some users as reliving their own birth Many users experience a dissolution between themselves and the "outside world".
includes the illusion of movement of static surfaces ("walls breathing"), after image-like trails of moving objects ("tracers"), the appearance of moving colored geometric patterns (especially with closed eyes), an intensification of colors and brightness ("sparkling"), new textures on objects, blurred vision, and shape suggestibility. the inanimate world appears to animate in an unexplained way.
echo-like distortions of sounds, a mixing of all sounds which makes it harder to discern distinct sounds, the feeling that what you're hearing is your thought, a general intensification of the experience of music, and an increased discrimination of instruments and sounds.
so, i think my answer is close, although there seems to be a lot more going on with the visual end of things.