BLAT is a bioinformatics software tool which performs rapid mRNA/DNA and cross-species protein alignments. BLAT is more accurate and 500 times faster than popular existing tools for mRNA/DNA alignments and 50 times faster for protein alignments at sensitivity settings typically used when comparing vertebrate sequences. (Source: Kent, W.J. 2002. BLAT -- The BLAST-Like Alignment Tool. Genome Research 4: 656-664. http://dx.doi.org/10.1101/gr.229202) BLAT is not BLAST. DNA BLAT works by keeping an index of the entire genome (but not the genome itself) in memory. Since the index takes up a bit less than a gigabyte of RAM, BLAT can deliver high performance on a reasonably priced Linux box. WWW: http://www.genomeblat.com