My mother got me to listen to the directors commentary of SG-1 and there are real gems in there.

For example, how the early seasons had a 1,2,3 use of the phasers. Zap 'em once, and they are incapacitated, twice and they are dead, and 3... cleans up the mess... They abandoned it later because it was "too convenient".

Also, take notice of the giant wrench that appears from time to time in the background scenes in the base.

Also, there are so many callbacks and references in every episode, you really can spend hours or days drawing lines through story elements to see how long running some jokes are in the later parts of the series.