I am now a (very junior) notary in the thawte Web of Trust. An assurance from me is worth 10 points towards the 50 required for a personal e-mail certificate with your own name on it.
More details are available for those who are interested.
[Updated 20100118: Thawte recently closed down their Web of Trust and stopped issuing personal e-mail certificates. This article is now of only historical interest.]