Portals, Self Service etc

Wow, where do you start with Self Service and Portals. So much has changed now, it is difficult to know what is what. 

FeatureYou NeedDescriptionHelp LinkCan use if already set upAvailable to set upReplace With
Public Solutions Show solutions on your website. A really really ugly way of doing it.https://help.salesforce.com/htviewhelpdoc?id=customize_publicsolutions.htm&siteLang=en_US(tick)(error)

Chatter Answers in Sites

Or Knowledge in Sites

Self Service Portal 

A way of putting all your self service options out on the web

A nice article about Portals http://www.shellblack.com/portals/self-service-portal/

https://help.salesforce.com/apex/HTViewHelpDoc?id=customize_selfservicejumpstart.htm&language=en_US(tick)(error)Chatter Answers in Sites
Customer Portal A newer version of the Self Service Portalhttps://help.salesforce.com/HTViewHelpDoc?id=customer_portal_setting_up.htm&language=en_US(tick)(error)Communities
Solutions Q&A topics for internal and web use    
Knowledge

Performance Edition

(EE additional cost)

A typical knowledge base. Not customer created. But customers can see it on your public website or on your communities.

See Knowledge

https://help.salesforce.com/HTViewHelpDoc?id=customer_portal_setting_up.htm&language=en_US (tick) 
IdeasProfessional and upAllow customers to submit and vote on ideas. Like the Salesforce ideas site. Use on communities or public sites

https://help.salesforce.com/HTViewHelpDoc?id=ideas_about.htm&language=en_US

https://na1.salesforce.com/help/pdfs/en/salesforce_ideas_implementation_guide.pdf

 (tick) 
Answers Q&A but other members of the community answer.https://help.salesforce.com/apex/HTViewHelpDoc?id=answers_using.htm&language=en_US(tick)(error)Chatter Answers
Chatter Answers A Q&A but other members of the community answer.  (tick)