If you`re tired of asking the same old stuff over and over again, buy a summary history book (you know - something like "History of the 19th Century" - a book that summarizes the historical highlights of every year within a century), ask for a page number and pick anything off that page. You`ll get plenty of different locations, characters, objects (the invention of the light bulb) and so on.
Instead of asking for something specific, you can also just start talking they mention as a scene starter. Asking for that much information may even be necessary for games like Day in the Life .
Be creative with the actual use of suggestions in a scene. Classic example is using the location `Bathroom` only to step through the mirror into a kind of Alice in Wonderland location.
Instead of just asking for suggestions before a scene, why not ask the audience to write down suggestions on slips of paper before the performance? Put these in a hat and just draw suggestions before the scene. Or stick them on a dartboard and have an audience pick the suggestion by `darting` it.
There is a long list of ask-fors at LearnImprov.com . On YesAnd.com you`ll find the Ask-For Superstore ( http://www.yesand.com/phpBB2/viewtopic.php?t=5275 ).