As per calls, theres a service you can get thru the telephone company that blocks all private callers.
Meaning, if they want to reach you, they have to use the *82 code to disable privacy, then call... which would leave a traceable called ID log as to whom called.
The camera thing would be nice.. however, I think it would be more fun to be a bit more aggressive... such as building an decorative overhang that contained a massive cold water container dumper (hmm, maybe instead use something sticky like syrup, or color dye !), (or maybe some sort of actuated -or manual- hose sprayer system) all filmed in glorious HD, and uploaded to youtube.