My old interest is to influece the brain to make it working more efficient.
One of the approaches is to learn complete relaxation, or in other word meditation. The book "Meditation für Skeptiker" by Ulrich Ott suggests a scientific evidence for this claim, and I decided to try.
I tried and failed. I wasn't able to understand if I was doing the process right or not. I wanted to have some tool which would say if the brain activity slows down or not. I searched for something like "eeg for home" but there were no such thing, and usual eeg-devices were very costly.
Recently I found the project OpenEEG.
The OpenEEG project is about making plans and software for do-it-yourself EEG devices available for free (as in GPL). It is aimed toward amateurs who would like to experiment with EEG.
Then I found an already built OpenEEG-based device from Olimex (Europa/Bulgaria). The total cost of everything what required was around 150 euro, the internet-feedback about the firm and theirs electronics was good. So I've ordered it:
Low cost open source EEG device, completely assembled, USB interface
I got the package in several days. Everything was good packed.
The only problem is to find which one is the passive electrode. All the 5 look the same. I decided that the passive should be simplier, and found exaclty one without some (amplifier?) chip. Don't forget to mark the electrode to find it again easily.