Comment by ryandrake
I've always liked the band Kraftwerk's [past] strategy for dealing with interruptions, from their Wiki page[1]:
"... anyone trying to contact the band for collaboration would be told the studio telephone did not have a ringer since, while recording, the band did not like to hear any kind of noise pollution. Instead, callers were instructed to phone the studio precisely at a certain time, whereupon the phone would be answered by Ralf Hütter, despite never hearing the phone ring."