I'm doing the low-carb thing too, and here's a bunch of stuff I keep handy.
String cheese (with 2 or 3 mini rice cakes for crunch)
Cottage Cheese (with 1 T. of Fiber One yogurt)
Tuna - mix with 1 T mayo & 1 oz cheddar cheese and nuke for 30 sec.
Salmon Pinwheels - find them at Target, with crab filling. Yummo!
Bags and bags of "steam in the bag" frozen veggies - I toss them with a little butter & feta cheese crumbles and eat 1 cup almost every night.
Lettuce wraps - wrap turkey or ham and provolone cheese in a lettuce leaf with chopped tomato and mayo. Delish!
Veggie dips - raw yellow pepper strips, cucumber and baby carrots go down really well - with a little sour cream mixed with dill.
Sausage & Cabbage - simmer hunks of polish sausage with chopped cabbage until the cabbage is fork tender.
I also buy a lot of pre-marinated pork loin - just heat and serve w/ veggies. I go to Sam's Club and buy huge bags of frozen chicken breasts and have about 20 low carb chicken recipes I make with them. Here's a few of my family's favs....
1. Marinate chicken in Greek dressing - Saute, then toss with steamed spinach & feta cheese.
2. Coat chicken with a mix of mayo & garlic salt, then roll in parmesan cheese (w/ a spoonful of breadcrumbs tossed in, if you like). Bake at 400 for 15-20 minutes.
3. Marinate chicken in Italian dressing. Saute w/ red & yellow peppers & chopped onion. Toss w/ parmesan cheese. I serve this to my boys over Pasta - but serve mine just with a salad.
Hope a few of these sound yummy!