I step away from the computer and go for a walk. Even if it's just to my mailbox. I also find that driving is therapeutic and the land around my house is very picturesque, very inspiring. So sometimes I'll find an excuse to drive to the post office in Eleva or Fall Creek, anything to get me away from a computer screen.
I also think it is crucial to read, read, read. Read old masterpieces, and new masterpieces. Foreign writers, poetry, comic books... I find a great deal of material in my local newspaper, as well.
The thing is, the real world is not a computer screen or Facebook or your iPhone. So I try to get outside my house where inevitably I encounter someone, witness something, or experience some sensation that spurs me forward.