1/2 lemon juice and 2 cups water in a spray bottle
1/2 cup vinegar or lemon juice, 2 cups water, 1/4 teaspoon vegetable oil based soap (such as Murphy's Oil Soap)
Mix 1/2 cup cornstarch with 2 quarts warm water. Apply with sponge then wipe with absorbent cloth or towel. Do not wash windows or glass when sun is shining on them or if they are warm. This causes the solution to dry too quickly creating unwanted streaks.
No-Streak Glass Cleaner:
1/4 cup white vinegar
1 tablespoon cornstarch,
1 quart warm water
Mix the ingredients and apply with a sponge or pour into spray bottle and spray on. Wipe dry with crumpled newspaper, buff to a shine. (Use crumpled newspaper instead of paper towels for lint-free results and as an eco way of reusing newspaper).
Rubbing alcohol is effective in place of glass cleaner.
Use club soda in a spray bottle for a streak free perfect clean glass cleaner, eyeglass cleaner, mirrors, tv and computer moniters. Spray on rag not directly on object. (courtesy of Deena, thanks!)