I became aware of Johnston and his eclectic and raw music mostly from the compassionate 2005 documentary about his life, The Devil and Daniel Johnston. Filmmaker Jeff Feuerzeig chronicled the life of the manic-depressive/schizophrenic artist, using a blend of home movies, Johnston's own audiotapes, vintage performances, animation and current footage.
Johnston recorded nearly a dozen albums and amassed thousands of sketches, and has among his supporters Matt Groening, David Bowie, Sonic Youth, Beck, and Tom Waits.
Watch the trailer for the documentary here which also gives a taste of his music.