If you don’t like having to switch to the Google Docs (s goog) website to monitor your account to see whether any new documents have been shared with you, check out Google Docs Notifier, a simple free Widows (s msft) utility that sits in the taskbar, displaying a count of unviewed Docs. Clicking the icon pops up a window displaying those unviewed Docs, which you can use to click through to the documents themselves in your default browser.
Although it would be nice to be able to log into more than one Google Docs account and I’d like to see a bit more visual polish (icons to help distinguish the different file types, for example), it does provide a very simple and easy way to keep tabs on your Google Docs account.
Google Docs Notifier works with Windows XP, Vista and 7. It’s an open source project that can be downloaded from Google Code.