The 23andMe DNA analysis kit is on sale for only $99 - normally priced at $499. Use Gizmodo's coupon code GIZMODO99 to get the deal.
Once the lab receives your sample, DNA is extracted from cheek cells in your saliva. Your DNA is then copied many times so that there is enough DNA to use for the genotyping step. Next, the DNA is cut into smaller, more manageable pieces. These DNA pieces are then applied to a DNA “chip.” The DNA chip is a small glass slide with millions of microscopic beads on its surface. Attached to each bead are “probes”—bits of DNA complementary to sites in your genome where SNPs are located. There is a pair of probes for each SNP, corresponding to the two versions of each SNP. Because two complementary pieces of DNA stick together, your DNA sticks to whichever probes match your versions of a SNP.
Here's a review of the analysis you get from 23andMe - http://paulstamatiou.com/review-23andme-dna-testing-for-health-disease-ancestry
I'll post some of my results once I get my analysis back.