Have the bioinformatic methods like sequence analysis, genome annotation, comparative genomics (and many others), been applied to solve problems outside the field of bioinformatics?
Of course! The perfect example is Gusfield book. Many of string algorithms came from bioinformatics. For example, sequence analysis algorithms are used in text editors.
PS: Algorithms on Strings, Trees and Sequences: Computer Science and Computational Biology, Dan Gusfield