I'm a poor source of modern information like current consumer ones, and never did build my own. I used to follow the openeeg mailing list, which has tapered of

I'm a poor source of modern information like current consumer ones, and never did build my own. I used to follow the openeeg mailing list, which has tapered off in the last couple years: http://sourceforge.net/p/openeeg/mailman/openeeg-list/ http://sourceforge.net/p/openeeg/mailman/openeeg-list/ (http://openeeg.sourceforge.net/doc/ http://openeeg.sourceforge.net/doc/) building one yourself was usually around $200 in parts but there were always interesting ideas to do simpler devices. You will find references to consumer ones people were considering, and responses that are helpful for figuring out which specs matter. I would also look for the names of new projects people are developing and maybe some of the hobbyist communities that are still active and debating the minimum specs for a budget device today..