>Some installs ask whether you want the app for all users or just the current one, but many don't. I have to users on my laptop, me at work, and me doing other stuff. I don't always want the same apps for both. Can I share/exclude apps after the install per user?

I guess what I really wanted to do was limit access to different users. I can essentially do that through the Start menu for each user:

Wikipedia...

"Users may add entries by creating various folders and shortcuts in the Start Menu folder, located in the hard drive. These appear in a separated section at the top of the Start Menu, or, if placed in the Programs sub-folder, in the Programs menu. In the Windows 95, Windows 98 and Windows Me, it is located in C:\Windows\Start Menu, or, if there are multiple users, C:\Windows\Profiles\username\Start Menu. In Windows 2000 and XP, the folder is located in C:\Documents and Settings\username\Start Menu for individual users, or C:\Documents and Settings\All Users\Start Menu for all users collectively. In Windows Vista, the folder is located in C:\Users\username\AppData\Roaming\Microsoft\Windows\Start Menu for individual users, or C:\ProgramData\Microsoft\Windows\Start Menu for all users collectively. In all examples above, username represents the name of the user. These places can be easily accessed by right-clicking on the Start button, and clicking Open."