Have you ever seen the top of a wall in most mexican towns?
Shards of glass. Seems a bit more effective.
Unless you have those outlawed instuments that can circumvent that security. Namely, a hammer(wrench, baseball bat, whatever) and a strip of good canvas (thick blanket, old jacket, etc...).
"You have all recieved youre last warning. I am in the process of currently tracking all of youre ips and pinging your home adressess. you should not have commencemed a war with me" - Aaron Rayburn
God those things are wonderfully medieval looking. Especially the guantlet of spears. I want those around MY house! Big spike rods, god imagine the fun! Especially if a moving platform was underneath them and the only way to get in was to jump with good timing.