Outputting signals from vvvv

there are many options for using a relay board with vvvv:

Built in interface nodes

vvvv directly supports several io interfaces: currenly there is a driver for the BMC meM-PIO USB interfacehttp://www.bmcm.de, and the Wiesemann&Theis Digital-EAhttp://www.wut.de.

The w&t interface sports 12 leds and industrial strength inputs/outputs which can direcly drive smaller lamps, and gets connected over standard Ethernet. It is not a cheap solution though.
The BMC interfaces and sensorbox devices are much simpler and connect via usb.

Midi to relay interfaces

Another option is using something out of the midi world - use a midiout node to send midi commands and connect the board via a midi port. the mtc from doepfer looks fine for that.http://www.doepfer.de/mtc.htm
See the Howto MIDI page for details

DMX to Relay interfaces (demultiplexers)

Use something out of the dmx world – there are so called dmx-demultiplexer boxes available. Which tend to be more sturdy and easy to use as the things from the midi world:
I found boards from soundlighthttp://www.soundlight.de/produkte/wg18/18_dmx.pdf and MA lightinghttp://www.lightpower.de/produkte/pdf/PG13_MA_pl.pdf but there are many others available
See the Howto DMX? page for details

RS232 Relay interfaces

There are several solutions for rs232 relais interfaces. conrad used to sell one, but i forgot the order code. check out also the devices for fischertechnik and lego construction kits. you can also connect the cinetix box via rs232.
See the Howto RS232 page for details

Photosensors

apart from that - glueing light sensitive resistors onto an old video screen is fun & gives many many opto isolated outputs at almost no cost.