Prank

[gaspode2002]

No: HPFGUIDX 80445

The whole prank thing doesnt add up in my opinion. There is something 
we have not been told. Although Snape has many personality flaws, he 
is neither stupid nor cowardly. He is also  very well versed in dark 
arts and a pureblood snob. It is inconceivable to me that he had not 
figured out that Remus was a werewolf. I wouldnt be surprised to find 
out that Snape went to the shrieking shack packing silver and that 
Remus was actually the one who was saved.

Gaspode (named for the famous Gaspode)

PS: Yeah, I know its not canon. For a long time it was canon that 
Scabbers was a fat lazy rat. Canon changes.