Just wanted to share some info...
If anyone is trying to work with "Blog by Email" and cannot setup a cron job on their server... and is struggling with Cronless Postie / Wp-Cron..
AFTER spending a lot of time trying to get Postie + Cronless Postie + Wp-Cron to work, I actually DID get it to work.. but found a simpler way to do this later, and kicked myself in the hiney for all the time wasted.
So, to get your "Blog by Email" to work, all you need is Postie OR just the actual WordPress WP-Mail.php AND a FireFox Extension/Add-On called "Page Update Checker" at http://pageupdatechecker.mozdev.org
"Page Update Checker" will visit either of the pages below, as often as you wish.
BUT.. the only downside is that your computer needs to be online.. and Firefox needs to be open!! You do NOT need to have a tab/page open on FireFox, for this Add-On to work, as it works in the background for you.
If you're not online all day, then forget it. You will need a Cron job then.
Hope this helps!!