Email / Newsletter Promotion
MailChimp - Great starter service for sending out newsletters. 2000 subscribers and 12,000 emails a month is completely free!
Web Site Optimization
WooRank - We use this sometimes but we take the opinion of seo automated analyzers lightly. WooRank let's you review one web site a week for free.
Icons, Royalty Free Graphics
iconfinder.com - We use this site pretty regularly, just be sure to pay attention to the liscense for each download before posting on your web site.
Software For Your Desktop
cutepdf.com - We have been using cutepdf for years now, install it and it acts as a printer so you can create PDF's from absolutely anything!