Ballista Tactical Systems has developed a rotating rail. The forward section of the rail can rotate in 45 degree increments with the push of a button. This can allow, for example, a bipod rotated around to 3 c’clock and a fore-grip rotated into the 6 o’clock position.

I think Ballista Tactical Systems needs to develop a new model where the forward section can be unlocked to rotate freely. This would be fantastic when using a bipod on uneven ground. Rotatable bipods are a feature of very high-end sniper stocks.