Nikon D3100 Cable to show live filming on computer?

I have a Nikon D3100 and I was wondering if there's a cable or method of showing what I'm filming on my computer while I'm filming. If the camera is pointed at me, I can't see the screen and therefore am not sure if the focus is right or if the framing is even right.

Nope

The Nikon D800 and D4 can do that, but not an entry level camera.

NOTE:

Your camera can only shoot video. Film requires that you use a 16 mm or 35 mm motion picture camera

Use a mirror and see if that helps.

Besides the no, you can't do film with this camera anyway since it's digital.

I don't know what ace is smoking, the Nikon D800 and the D4 are not the only two cameras that can do this. There are several that can send video out via the HDMI, like the Sony A99 for example, uncompressed too if you want it.

This ability is not available right now for entry level dSLRs like the D3100 and it probably won't be even next year or the year after. Camera makers try to keep entry level dSLRs very basic to keep the price down, that's why entry level dSLRs still can't tether, still don't have a real pentaprism vs.a penta mirror, some things won't trickle down to keep the price competitive, and considering 99 percent of casual users of dSLRs will never use these extra features.