Red Sweater has released version 4 of MarsEdit. I use the application every day. $24 upgrade price was a no-brainer. It was a one time cost that adds the license to my MacBook Pro and iMac without having to buy it twice. The fact you can use it as a journaling tool offline for free forever is a great thing. You only pay when you want to publish to an online service. John Gruber linked to the 2005 review of version 1. http://www.atpm.com/11.01/marsedit.shtml
Amazing how much this simple concept has evolved. I couldn’t live without it.