Every time we mention PeeKaWho or Aerize Email Alerts on the site somebody invariably asks for a comparison between the two applications. Personally I get too much email to use either of them regularly so I can never really comment.
Jonathan over @ BBCool did all of us a favor and put both of the applications head to head in a comparison. PeeKaWho comes out a little ahead in the clash but personally I found the details of the review to be the best part. Jonathan does a great job of breaking down each app and its features.
Check out the comparison at this link and let us know which app you prefer in the comments.
Thanks DavidB for sending this one in!