Ingredients:

2 cloves of garlic
1/2 pound smoked salmon
6 oz. sour cream
1 1/2 cups crushed tomatoes
1/2 tsp sugar
salt, pepper, oregano

Cut or press garlic, fry in a little oil. Cut salmon into small pieces, add to garlic, fry until color changes. Add sour cream, tomatoes [1] and sugar; simmer for a few minutes; season to taste. Serve over spaghetti.

This isn't entirely cheap (unless you can find low-priced salmon), but easy to make and yummy. At least I've never had complaints. :) Please note that this is one of the few pasta dishes that are _not_ improved by parmesan cheese.

[1] If you use fresh tomatoes, put them in boiling water for a moment and peel them.