Aaron Wormus has dug up some old notes that he made at the International PHP Conference back in 2005 on the topic of Unicode in PHP that he wanted to share.

He mentions:

• A case study of an online survey generator
• info about Unicoding and UTF-8
• Iconv and mbstring
• and the migration of the application to support Unicoded characters (a nine step process)

And also, a word of warning:

Everything was much more complex than expected. Don't do this because you think that UTF-8 is cool, it's difficult, not well supported in PHP, and don't do it without needing it. Don't do this without a CVS.