I've been using GNOME 3 for a while and I miss something like KDE Activities.
A nice explanation about KDE Activities can be found on this page:
[...] when you take the time to learn about Activities, you'll find them a natural extension of the desktop metaphor that just might help you to work more efficiently.
Activities are a super-set of Virtual Desktops. They don't replace Virtual Desktops -- in fact, each Activity can have its own set of Virtual Desktops if you choose. Instead, Activities are alternative desktops, each of which can have its own wallpaper, icons, and widgets.
The most common way to use Activities is to create one for each general task that you do. For instance, you might set up one Activity with all the apps and widgets that you need for coding or writing. Another desktop might have your web browser, email reader, chat application and other Internet applications. Yet another might be your dumping ground for articles that you want to read later.
Alternatively, you might set up Activities according to location, with different desktops for work, school, and home. [...]
Is there something like that for GNOME 3? I would like to have an standard activity and another activity for studying.