How's this for strange: Secret of Monkey Island has been swinging back and forth from $10 to $5 since it's introduction.
See at AppShopper, a site I just discovered.
EDIT: it appears that Aspyr plays with the prices constantly. KOTOR and CoD4 are already back to $20 and $50 respectively. Looking at the AppShopper dates, the price is always cut in half on a Sunday or Monday and raised back the next day.
Speaking of KOTOR, the App Store system requirements have been jacked sky-high, with neither Intel nor NVidia integrated GPUs supported, even though the comments include several people saying it runs just fine on those systems. I can't believe a game from 2003 can't play on a recent iGPU.