We eat canned tuna a lot. Not quite so much since the wife got the preggers because of mercury issues, but before that we had tuna sammiches and tuna casseroles regularly. We've tried the canned salmon, which works fine. Canned chicken I haven't tried but I doubt it's much different than the tuna.
Any of those work great in a sammich in 10 minutes or less (mix with mayonnaise to taste, then apply to bread). Some people in my family have something called creamed tuna on toast, which is canned tuna (or whatever) plus cream of chicken warmed and spread on toast. Not bad if you prefer something warmer. The tuna casserole I make takes up to 40 minutes, which isn't what you're going for.