Here's my workplace: The iPad to the right runs Set List Maker and displays the set list, lyrics and chords (for the ususal what-the-heck-was-the-next-chord-moments ;)) and flys in a few sound samples. The other iPad is for a VJ app TouchViZ (http://hexler.net/software/touchviz/) that displays all our video sequences and a live camera picture from time to time over WiFi. Not on the picture are the two other iPads running Set List Maker: One for the violin player who uses it to display his musical sheets and the most important iPad at the drummer's place. Besides from being used as metronome, this one sends MIDI program messages and MIDI clock to my guitar processor Line 6 POD HD500 (http://line6.com/podhd/), to the light show controller and to the TouchViZ app to switch the video sequences. We also use the iPads to remote control the monitor mixer Mackie DL1608 (http://www.mackie.com/products/dlseries/apps/) for the in ear systems of the vocalists. ...and it all works (most of the time)! :)
More info: www.facebook.com/t-rock