Very interesting web services

Below my preferred web applications at this moment:

• Google reader : powerful feeds aggregator (it lacks in searching...)
  
• iGoogle : personalized home-page which I extended with several widgets:
• Google calendar (see below) widget
• ANSA news widget
• Punto Informatico widget
• Tree frog widget
• I also customized the theme and now it displays different backgrounds according to the weather in my city
  
• Google calendar: powerful calendar and agenda, with SMS notifications (free!)
• Last.fm: listen to your music and look for new artists