I am getting tons of this too and to delete these type of entries as quick as these f*ckers submit this I go to phpmyadmin and deal with it one time. If not for this, I reckon I'd give up. On the type of links themselves - I was particularly curious too so proceeded to enter one of the urls into my browser and something started to download! Not sure what it was I turned off PC quicktime..... .
I will typically just delete them - sometimes curiosity gets the best of me. But I always wonder what the point is for the pointless submissions. You all have offered some good insight into it though!