Plakaty.ru's Museum of Russian Poster has an impressive collection of advertising and propaganda/agit-prop posters from the early twentieth century. Like some of the American advertising I've posted, particularly those from the 1940s, many from the collection are veritable works of art.
I can't read Russian, so I can't confirm the little amount of translation on the site. The graphics more than make up for this, though. Here are a few links to my favorite advertising, in chronological order:
1. Cakes of S. Siu & Co. - depicting the annual 'biscuit rolling' competition (1900)
2. Demand Sausages Everywhere (1937)
3. Tinned crab in a neat molded salad shape (1938)
4. Ice Cream: Demand Everywhere (1938)
5. A Chaplinesque cake hawker (1941)
6. A mother penguin serving a fantastic array of ice creams (1951)
7. A seal holding up more ice cream (by the same artist as last ad) (1954)
8. A cheerful mélange of vegetables (1954)
If strange foods are more your speed, take a trip over to my new favorite site. Retro Life is an exceptionally nifty discovery of mine. All lovers of less appetizing foods should read through the recipe oddities where the author has done nothing short of recreating these odd marvels, including Curly Wurly favorite, the Perfection Salad!