Which web services are useful, add user value and reduce development effort for a new web site? Here is what I can think of so far:
- uservoice: manage customer feedback
- OpenID (sites like AOL, google, MySpace...): OpenID allows your users to use your site together with other sites as if they were one: Login just once.
- gravatar.com: Show the faces of your members
- google site search: Let visitors search your content
- twitter: real-time news for your members
- blogs, wikis (Wikispaces, tiddlyspot): keep your members up-to-date; create communities
- github: share code with your members (if you are a programming-related web site)
- stackoverflow: answer users questions (again: only if your site is programming-related)
- google maps: show locations
- paypal: simply handle online/credit card payments.
- captchas: keep spam off your user-comments
You get the idea: I am not looking for "Cool toys to play with on my site" but for services to get a job done without getting dragged down with all the details --- leaving me some time to focus on what's unique on my site. Please add to that list...