For the last few months I have been keeping tabs on what I've been eating. There is this great site called The Daily Plate, now operated by LiveStrong, and it shows you what you eat.
Basically you type in "turkey sandwich" and tons of options to choose from come up. Also, many brand names and restaurant foods come up. It's awesome. You can add up what you eat everyday and see how much Fat/Carbs/Protein you are getting. You can also change the settings, using your weight and height, and say you want to lose/gain blank # of pounds, and it will give you the calories you need to do so. I love seeing halfway through the day where I am calorie wise... from a big breakfast or a small one. I am just starting to add my fitness log, which also helps track calories and fitness.
It's really interesting to see over time what you eat a lot and what's in it. I am not methodical about this site--I think I've tracked 4 days in a row faithfully. But it does help with keeping in good health and good shape.