[dougp]

This is hardly specialized knowledge but in 24 after every commercial break we were treated to a digital clock displaying the current time. They were using some digital clock number font that was not monospaced so the numbers spread and shrink right in front of you as the clock "ticks", which of course would never happen on a real clock face.

[chopsueyar]

This is the only implausible part of '24' I noticed too.

[nfriedly]

Also, if you noted the time on the show before and after the commercials, less time passed in the show than in real life.