OK, two types of missions involving murder would be cool.
1) Accessing a global medical database, mb at the top level of security, there would be the option of editing the stuff a guy takes, and so, you could alter the doses to be lethal by adding chemicals and whatnot.
2) Another possibility, assuming that Onlink's in the future, is that all cars would have a computer inside of them. You could hack into the car database, or whatever, and screw up the computer of someone's car so it crashes.
Valid, or just plain sick and wrong?