If you don't have one already don't wait any longer. It's the greatest email service around. You can't beat the interface and it's very reliable. Only SpyMac can compete with the 1GB space. For a free invite email me.
Click for commentary and all the tools you need for gMail.
Designers working with hi-res images need bigger storage space and bigger bandwidth than the average Mac user. We need a bigger email account as well. gMail gives you 1GB storage space and it can send attachments up to 10MB, so you'll have plenty of room to send and receive zipped artwork. Hopefully the 10MB attachment size limit will go even higher in the future.