A good share of what you'll find here are mounting brackets for Behringer speakers, like the WB208 Black Wall Mount Bracket for EUROLIVE B208 series speakers and WB210 Black Wall Mount Bracket for the EUROLIVE B210 series. Those two are also available in white (the WB208-WH and WB210-WH brackets, respectively), so you can make your speakers look as good as they sound. Maybe it's not a speaker you're looking to mount, but a P16-M mixer... in that case, you'll be all set with the Behringer POWERPLAY 16 P16-MB Mounting Bracket, which easily secures to any standard microphone stand.
Some of Behringer's accessories are a bit more in the vein of active electronics, like the S16 Digital Snake, TU300 Chromatic Pedal Tuner and BTR2000 2-Channel RACKTUNER and Metronome. On the other hand, if you're simply looking for is a way to power up your stompboxes, check out the Behringer PSU-SB 9V DC Power Supply. Planning an international tour? It might be a good idea to bring the Power The World PSU-HSB-ALL Multi Power Supply along for the trip as well - it's versatile enough for a full European tour and, what's more, it can handle up to 20 pedals.
Whichever of Behringer's accessories are right for your needs, you can rest assured that they're more than up to the task. We would expect no less from a manufacturer as well-known as Behringer, after all, so when you're searching for the power adapters, mounting brackets and other accessories to complete your pro audio setup, this is a great place to start.