How to view how many pictures I can take left on my Nikon d3100?

I have a Nikon D3100 and I want to know how many more pictures I can take I have an 8 Gb memory card but I can't seem to find a place on the camera where it will tell me how many pictures I can take. Please help! Thanks!

Added (1). Unfortunately I'm traveling in Europe and do not have a computer with me

You can take hundreds of photos in the jpeg format on a 8 GB card! Not a good idea to store photos on a SDHC card though. I upload mine after each shoot.

First, you need to copy all your images from the memory card to your computer at the end of each shooting day.

Once they are safely on your computer, you need to format the memory card using the cameras format feature.

When you look through the viewfinder, on the lower right hand side in some brackets, you will see an number. That number indicates how many images you can add to your memory card. Look on page 6 of your user manual

An 8GB card can probably hold thousands of images, depending on your quality and size settings. If you can't bring a computer, keep the SD card in the camera at all times and try not to delete photos from the camera. You can worry about that sort of stuff when you're back home again.

The camera might be showing you a number like "1.4k" or "3.2k", which mean 1400 and 3200 respectively. The count is visible on the rear LCD and in the viewfinder, set in brackets on the bottom right corner.