Online Mendelian Inheritance in Man (OMIM) www.ncbi.nlm.nih.gov/Omim/
Information about human genes and disease
The SNP consortium snp.cshl.org/
A variety of ways to query for SNPs in the human genome
UCSC Genome Bioinformatics genome.cse.ucsc.edu/
Reference sequence for the human and C. elegans genomes and working drafts for the mouse, rat, Fugu, Drosophila, C. briggsae, Yeast, and SARS genomes.