For those who want a program that does this well, I find that "mplayer" is decent at speeding up the things it plays. '[' and ']' alter the speed, and the intial speed can be set with eg. "-speed 2.0" on the command line, though I find that too fast.
One generally wants to correct for pitch changes with the "scaletempo" audio filter. This can be enabled with "af=scaletempo" in a config file, or "-af scaletempo" on the command line.
(One can also use the "mencoder" version of this to create sped-up files for use on other devices).
Audacity also works for this purpose.
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