Geoloqi is an iPhone app with some great location sharing features. The features of Geoloqi include Geonotes, automatic Foursquare checkins, and private real-time GPS tracking.
Similar to Glympse, Geoloqi allows you to share your location with those you want to, for a limited time. Your friends can then view your location on a Google Map only for the time that you have defined.
The Geonote option allows you to leave a message in a location and have it e-mailed, texted or pushed to you when you get to that location. You can therefore send yourself a message reminding yourself to pick up milk. You can set the location so that you receive the Geonote when you are passing the store. Or you could leave yourself a note at work reminding yourself about an important task.