Actually, if you are corresponding with me, it's marginally useful if your email leaks your IP. It means I can select Show Original in Gmail and see your X-Ori

Actually, if you are corresponding with me, it's marginally useful if your email leaks your IP. It means I can select Show Original in Gmail and see your X-Originating-IP header. Then I can run your IP against, for example, MaxMind† and see if you are (1) at home, (2) at your office, (3) visiting your in-laws in Santa Fe, or (4) somewhere else. Of course, there's a slight asymmetry: Gmail does not supply the X-Originating-IP header. So you can't, in turn, look me up on MaxMind. But, if you are my Gmail correspondent, you probably don't know about the header, anyway. †http://www.maxmind.com/en/geoip_demo http://www.maxmind.com/en/geoip_demo