Benefits to having two pfsense boxes connected to each other?

[felesaerius]

Hello all, I'd tried asking this in IRC, but never got an answer. Is there any benefit to having two pfsense boxes know about each other from different networks? I set up a pfsense box at my friend's place, and I have one myself, we're both on comcast business, but I don't know what benefit there would be of the two knowing about each other. Any? Please let me know!