lalign is a web app to compare two sequences looking for local sequence similarities. lalign/plalign use code developed by X. Huang and W. Miller (Adv. Appl. Math. (1991) 12:337-357) for the "sim" program. lalign will report a specified number of alignments (the default is 10) between the two sequences lalign shows the actual local alignments between the two sequences and their scores, while plalign produces a plot of the alignments that looks similar to a 'dot-matrix' homology plot. Registration not required.