RE:Vision Effects ( has released Twixtor
Express for Final Cut Express. Twixtor enables users to speed up,
slow down image sequences.

In order to do so, Twixtor synthesizes unique new frames by warping
and interpolating frames of the original sequence, employing
RE:Vision Effects’ Academy Award winning technology that calculates
motion for each individual pixel. This simpler-to-use version has
been engineered for Final Cut Express users and is specially priced
at US$169.95.

Twixtor Express is available as an FxPlug plugin for Final Cut
Express 4.0.1 and up. Note that Twixtor Express isn’t available for
Final Cut Pro, but the regular and Pro versions continue to support
Final Cut Pro users.