Awesome icon needed for new online service

Spanning Backup

Spanning is a successful indie software and online services company with two shipping products: Spanning Sync (http://spanningsync.com) and Spanning Tools (http://spanningtools.com). We're about to announce our third product and want an awesome icon to go with it.

Our target audience is people who use Google Apps (Calendar, Contacts, and Docs). Our web app (not yet public) has the feel of a modern (AJAXy, "web 2.0"-ish) site, and our users appreciate good design.

Spanning Backup is an online backup service, so the icon should reflect the idea of storing or protecting your Google data. We like the basic concept of this mockup (but it uses a stock photo, which won't work):

http://spanningsync.com/images/span…toicon.png

The design should incorporate the capital "G" from the Google logo (the font is Catull regular) in the design. (Trust us, all our others do and Google doesn't seem to mind.) The design should not include the name "Spanning Backup"--it's an icon, not a logo. See the Spanning Sync icon for an example of how we convey the "for Google Apps" part of the service name:

http://spanningsync.com/images/span…on-128.png

The full-size icon should be 512x512 pixels with a transparent background (but doesn't have to be square), and should scale down well to 32x32. The icon should be at least somewhat visually consistent with those for our other two products (for instance, we seem to like blue but it's not a requirement):

http://spanningsync.com/images/span…on-128.png
http://spanningtools.com/mac/images…on-128.png

Here are some icons we really like for other products:

http://static.arstechnica.com/apple…on_300.png
http://infinityandbeyond.files.word…o-icon.jpg
http://www.google.com/landing/chrom…e-icon.jpg

The files we will require are:
Web file format - .png and layered .psd (RGB)

Original work only please. Please do not use any stock images or clip art, or of course any copyrighted material.

We can't wait to see your design!