The first 2 Gnome panel backgrounds I'll show you have been created by Cláudio Novais (thank you for the suggestion!) and you can use them to get a glassy Gnome panel.

Here are the 2 Gnome panel backgrounds:

This second panel background works best for the bottom panel but I don't have one so that's why it looks a bit weird in my screenshot. To use this panel background, right click this image and select "Save image as":

Both of the above two Gnome panel backgrounds are semi-transparent so they will inherit the color of your wallpaper (but the image will be darker for the panel since it's semi-transparent).

After saving the background images to your computer, to use a Gnome panel background, right click on a panel, select "Properties", on the "Background" tab select "Background image" and browse for the image you have just saved:

1. There is an entire pack of Gnome panel backgrounds at Gnome Look:

This isn't something new, but I for one didn't know what the "Drawer" Gnome panel applet does so I thought I'd write about it.

If you're like me and want to have all the commonly used applications one click away, you probably have a lot of launchers on your Gnome panel(s) (I only have one which makes it even worse). But you can create drop-downs for these launchers, so that they take up a lot less space, and you don't even need to install anything. Here's how: