The sawblades are designed to literally chop through anything and everything that is in your way. Oh, what's that, a wooden sign blocking me from the next area? *SAWBLADE* (yeah, that's the sound a sawblade makes when it destroys shit). Got a group of ravenous zombie fuckers who want to tear you limb from limb? *SAWBLADE* Now, none of those bastards have legs anymore. On top of the destructive power that the blade has, it, in essence, has unlimited ammo, as the only way to lose the blade is to...well, lose it. The blades can constantly be picked up and reused after decapitating a row of zombies, again and again and again. The sheer amount of destruction capable from these blades is astounding. I've never had more pleasure using a weapon before as I did using those blades. I can remember my proudest moment on the way to achieving the "Zombie Chopper" achievement: towards the end of the level, you must wait for Grigori to shuttle over an elevator to the rooftop you're on, so you can progress in the level. While he does that, what seems like an army of Fast Zombies descends upon you. At first, I thought I was well and truly fucked; my last sawblade was 3 stories below me. Luckily, I was able to find a previously-shot sawblade a few houses back, and, after having shot and retrieved the blade about 15 times, finally destroyed the entire group of zombies. I literally leaped out of my chair in excitement, feeling like I had performed Ash-like feats of zombie termination.
Now, of course, if you aren't an achievement whore, you can play through Ravenholm normally. But, to get the most enjoyment out of the level, and to add 25 points to your Gamerscore, you MUST use only your Gravity Gun in Ravenholm. Believe me, when "Zombie Chopper" pops up on screen, you'll be more proud then ever before.
Fuck, now I gotta go play HL2 again...