Is it possible to disable Versions for all applications?
I guess you're rather referring to Autosave. This post describes the difference.

To disable Versions, I posted the (maybe risky) procedure here:

How to disable Versions in OS X Lion

However for Autosave the easiest work-around might be to use "System Preferences" &#x2192; "Keyboard" &#x2192; "Keyboard Shortcus" to define a keyboard shortcut (I used  &#x2318; &#x21E7; S) for the programs that have Autosave support and the "Duplicate" option in the menu:



For Textedit it will then look like this:



So you would press &#x2318;+&#x21E7;+S, which gives you a new duplicate window and then &#x2318;+S to save as new filename.

However, you original document will also (continuously) be saved and end up in the state where you created the duplicate - and without Versions (or Time Machine) you won't be able to recover earlier states as soon as you close your original document or the program.