Bottom Panel is a new GNOME Shell extension which, as the name says, adds a bottom panel to GNOME Shell. The panel includes a window list, workspaces switcher which you can right click to set the number of workspaces and a button to display the message tray (because the tray hot corner is hidden by the panel).
Here's a video I've created using this extension under Fedora 15:
Because the workspaces are aligned horizontally on the panel, the keyboard shortcuts for switching workspaces will also change to Ctrl + ALT + left/right.
There are a few issues with Bottom Panel GNOME Shell extension though, if you use dynamic workspaces: in my test, the dynamic workspaces work randomly (they only work sometimes). Also, you can right click the workspace switcher to set the number of workspaces - but make sure you only increase/decrease it by one or else it won't work.
The above issues are because the extension was designed to be used with the "disable dynamic workspaces" GNOME Shell extension and indeed, if you use this extension, the Bottom Panel extension works perfectly: you can right click the workspace switcher and set any amount of workspaces.
Bottom Panel is an extension developed by Ron Yorston and is a part of his "GNOME2-like user experience for GNOME Shell" extension pack.
To use the Bottom Panel GNOME Shell extension, download the extension pack somewhere like your Downloads folder (don't extract it in your home directory or else all the extensions in this pack will be installed), then press CTRL + H to be able to see hidden folders and navigate to .local/share/gnome-shell/extensions (this folder hieractly is created by extracting the extension archive) and copy the "Bottom_Panel@rmy.pobox.com" folder to your ~/.local/share/gnome-shell/extensions/ directory.
Download Bottom Panel GNOME Shell extension.
Thanks to John Stowers and Charles Bowman for the tip!