[chirp_users] Dongles ?

I hope this is an acceptable question for this list. I don't know any other place to ask for this help. A local county emergency manager has told me about an inexpensive magic ( to me ) dongle type rf reciever that plugs into a usb port. It has a jack for an external antenna. Supposedly this device can recieve a huge amount of frequency spectrum AND trunked systems that also uses p25 digital signals. If anyone has links to this device that would give me the complete info on this thing, I would greatly appreciate you. Thanks In Advance.