I think that my body currently needs at least 7 hours of sleep for me to be fully alert and at my best. Are there any methods by which I could get less sleep and still feel and be at my best? (E.G. specific diet, meditation, methods for better quality sleep)
The Polyphasic Sleep method is based on the sleeping phases and takes advantage of the phase which gives rest to the brain, the REM phase. The idea of the method is to sleep only 4 hours a day by taking small naps (20-30 minutes) every 4 hours of the day. The schedule is hard to follow, as you must take naps during the day.
I'd suggest you to first read several people's experiences with this method, before trying it (also, take care of the medical precautions!). Here's a day-by-day log of what happened while following such schedule: http://www.stevepavlina.com/blog/2005/10/polyphasic-sleep/
One more discussion here: http://www.kuro5hin.org/story/2002/4/15/103358/720
For increasing the quality of sleep, this information was helpfull for me:
The article by Dr. Wozniak is very detailed. He writes about the sleep cycle
The post by Steve Pavlina is a practical guide how you can train your brain