If you use Google services such as Gmail, or Google Calendar, here's a free, simple utility you'll most likely want. Googsystray (free) sits in your system tray and lets you know when you've received new mail, when a new appointment has been made, or when an existing appointment or deadline needs your attention.
If you are a Gmail user, for example, Googsystray will display a list of your most recent messages, including the sender, subject, and time and date the message was sent. You can mark the message as read, mark it as spam, or delete it. Or you can click the message to launch it in Gmail.
Googsystray works with a wide variety of Google services, including Google Voice, GMail, Google Calendar, Google Reader, and Google Wave. It's exceedingly simple to use. Tell it which service you want to check, enter your Google user name and password, and then configure each service--for example, whether to play a sound when fetching incoming mail, reminders, and voice mail. Anyone who would like their Google service to come to them--as opposed to seeking out the service themselves--would do well to give Googsystray a try.