Gmail rocks when it comes to online e-mail services. They just added something more to the interface to make things even more simpler in managing e-mails. Now when you are reading your mail there is a small button which says Reply (with a small arrow next to it). When you click on Reply it will simply open the Reply screen but clicking the arrow gives you a lot many more options. Earlier to access these features you would have to click on Show Options and then pick the feature from a cluttered layout. This little menu makes things much easier.
Kapil's Korner 
Use Firefox 2 browser. It has spell check built in and irrespective of which page u r in the spell check works.