How to Get 152/150 in PQ!

Well by 'is' you mean 'was' then yes it was possible to get 152 points out of 150...

There were supposedly two possible ways to do this according to random internet chatty/walkthroughy things about the game.

The first and most convincing is that, after you kill Kerrek, you can go back to Hidden glen and get a second arrow. You would get the arrow back in your inventory (so it'd be dark type, not the light-not-in-your-pocket type) and you would've gotten two bonus points.  Unfortunately they fixed this glitch (doesn't seem like a glitch though...) and now when you get your second arrow, the game puts it back in our inventory and says that your probably trying to get more points.
Because this deals with the inventory, fixing the arrow glitch probably also caused the mysterious ??? in the inventory. The ??? that can never be found, and it supposedly was the Map that you get no points for, but is obviously in your pocket.

The second also possible source of extra points is giving the baby (or the funnier 'drop the baby' like in my walkthrough) more than once. Supposedly this would give you extra points (obviously you couldn't get extra pills, like arrows though). I heard you could do it infinitely... but that doesn't seem right or random people would have been bragging about like 700/150 point games... and also it shouldn't really affect you inventory... so i'm not sure how right people are about this glitch...
But it too has been fixed, so homestarrunner.com is being the Points-Nazi:
 "No points for You!"