Here's something I noticed in Crysis (Demo)
When you have the fists out with maximum strength enabled, try hitting your melee key instead of just pushing the mouse button to punch, the striking power seems to be ten fold, you can knock cars flying.
Not sure if this is a bug or not.
Another thing i noticed is the firefights seem to be a little harder on the 'Hard' difficulty than on 'Delta'.
I have completed the demo a bunch of times now on Hard and on Delta, maybe I am just imagining it though.
Actually, overall I find the game to be a little easy, even on the hardest difficulty, especially with all the suit powers.
I have taken to setting challenges, like completing the whole level with just the pistol and/or with no suit powers.
Core 2 E6700
2 Gig Ram
2 x Leadtek 8800GTX SLI