Google suite of web apps

I have gmail, google voice, and wave. I now have notifiers for all of them in Chrome via the new extensions, which is great, since I don't need to have 'a email app open' or, have a gmail tab open.

Any time they light up or signal me, I hit one, and bam, I get a small preview, and I can just hit the button and go right to that new content.

The other cool thing everyone should try is using google docs with shared permissions. A friend and I were banging out ideas in a spreadsheet (extrapolating Moores law to 2030), and its a very compelling thing to see cells fill in real time, or have your own formulas corrected. Then, to discuss the results of the spreadsheet. Each person is at their own computer, without having to share a screen or keyboard.

Another great use for googledocs is resume proofing. Another friend of mine was worried about his resume, so he shared it on docs. I was able to fix spelling errors and add comments containing questions to him to mull over later. They recently added MS Word compatibility as well.