[stax76]

I finally resorted to a batchfile and some process list trickery to get the process priority down

you can control the command shell

http://www.microsoft.com/technet/arc.../shellscr.mspx

List<string> jobs = new List<string>(new string[] {"notepad", "notepad"});
using (StreamWriter sw = new StreamWriter("jobs.bat")) {
	sw.Write(string.Join(Environment.NewLine, jobs.ToArray()));
}
Process.Start("cmd", "/k start /wait /low /b jobs.bat");