The Nerf Switch Shot EX-3 was a gimmick blaster released in 2008 in conjunction with the Nerf N-Strike and Nerf Elite video games. It is essentially a Nitefinder with a removable firing system which could be replace with a Wii mote in order to play the games. They came in yellow for the N-Strike game and Blue for the Elite game.
The internals are nearly identical to a Nitefinder's, with the exception being that they can all be removed in one small package. The fact that the entire firing system is easily removable and is held together by only four screws makes this blaster easier to mod than a Nitefinder as long as you don't plan on rebarreling it. The small size of the firing system also means that it could easily be integrated onto something.
In comparison to a Nitefinder, the front is bulkier but more rectangular, making it easier to make a holster for, the handle is smaller, and it has its tac rail on the bottom instead of on the top. This means that most attachments are useless, but the Stampede Bipod does fit well and is fairly comfortable.
This Switch Shot is modified with no AR, a seal improvement and a spring addition. It hits 45-50', which is about what I would have expected out of a Nitefinder with similar mods. If you are interested in finding a Switch Shot, you might be able to find one at GameStop for a good price.
Size Comparison to Nitefinder
Firing System removed
Stampede Bipod attached