Gmail: mail + contacts. Easy to sync with my iPhone.
Calendar: I have my personal calendar + our ‘Friends events’ calendar (for parties and events) + my gf’s cal all in one nice view.
Notebook: Great for jotting down things like passwords, notes while on the phone.
Documents: I keep all my docs with Google, even my finances. And I don’t think I am crazy.
Reader: read and organise your fav RSS feeds.
Latitude: give your location details, and see where your friends are. (still waiting for the iPhone version, aaargh!)
ig: dashboard with gadgets (covering almost all of the above functionality), which just doesn’t feel to good, but I use nonetheless. Usually for a quick overview on mail, tasks and feeds.
Remember the Milk
Something that is still missing in the Google suite: a task manager that can do GTD. (Tip: to do that in RTM, use tags as projects.) You have to pay for a pro account ($25,- per year) if you want to sync your mobile device using their so called ‘MilkSync’.
The best photo sharing website in my opinion. It recently added video functionality, so now it kicks even more ass. If you want to share more than 200 photos, you have to go pro for $30,-. I think it’s worth it. I use it heavily and when you’re a pro member there are many other advantages: unlimited upload, upload originals (< 10 MB). I have my Flickr photo’s wrapped into my site (see photos section) by means of a wordpress plugin.