RANDOM.ORG - RANDOM.ORG offers true random numbers to anyone on the Internet.
SendRecurring - SendRecurring allows you to setup, send, and maintain scheduled email reminders.
Random Number Generator - Randomly generate integers or floating point numbers within a given range and specified discrete or continuous statistical probability distribution.
Recurrr - Send recurring emails
RandomPicker.com - RandomPicker.com helps you draw winners for your contests, giveaways or raffles.
FollowUpThen - The simplest way to schedule an email reminder