For all the amazing advances that the computing industry has brought us over the years, some of its most pivotal moments are memorable for all the wrong reasons. Not every idea can be a winner, and not even Microsoft can avoid every misstep. But as they say, those who forget history are doomed to repeat it -- then again, others just keep screwing up. n the interest of schadenfreude, here is a look back at the last 20 years' worth of blunders, fumbles, also-rans, and downright disasters you may have forgotten about -- or wish you could.

Top tech flops Nos. 21-25:Top tech flops Nos. 16-20:Top tech flops Nos. 11-15:Top tech flops Nos. 6-10:Top tech flops Nos. 1-5: