I always stock canned tomato products, especially in winter, when they are much better than most of what's available fresh; canned pumpkin; hominy; and chipotles in adobo. I sometimes buy canned or jarred artichoke hearts, hearts of palm, roasted red peppers and water chestnuts.
For convenience's sake, I also usually keep canned beans as a backup when I don't have time for long soaking and cooking. On certain other products, such as corn in winter, I'll weigh the prices of canned vs. frozen -- there's not much difference so I buy what's on sale. (During summer, I only buy fresh corn.) If you wrote canned vegetables off in favor of frozen years ago, you might give them another try, changes in technology have improved canned versions quite a bit.
Peas, however, are almost like three different vegetables -- fresh, frozen and canned. In season, when I can get them, I'll buy
fresh peas; otherwise, I prefer frozen for most uses.
The canned vegetable I use that shocks foodie sensibilities most is canned potatoes -- they're a great time saver for hash browns, fried potatoes, oven-roasted potatoes, etc.