Ask HN: What are your memories of the most overhyped startup failures?

I'm curious to read others' impressions of which startups seemed so promising or hyped to change the world, that ultimately failed. In my own memories, two stand out,

Transmeta which was supposed to revolutionize CPUs with dynamic instruction sets, and hired Linus Torvalds for a bit and then disappeared. From what I remember their CPUs were just too slow.

The other is Magic Leap, which seems to have just faded away into obscurity when everyone say their stuff and said "Meh."

Maybe my impressions are wrong. What others do you remember?