Everything is better with cheerleaders.
Although technically a rod, one of my all-time favorite items in the DMG is the immovable rod (I've always thought of it as more a wondrous item myself). It's one of those things that I like as a DM because it's true power and usefullness is dependant upon the creativity of the players. In my campaings I've always enjoyed items like that more than ones that just simply give a bonus to something.
Besides a still chuckle to myself when I think back on a time when a PC, hands tied behind his back, his head placed up against the back of a chair, and an immovable rod placed into his mouth pinning him in place. When the rest of the party found him one PC was quick to say, "Hold on a minute guys, he's enjoying some alone time." and walked out the door. Still brings tears to my eyes. Although I have a warped sense of humor.