This Javascript (jQuery, though likely easy to do with pure Javascript) + PHP code takes a bunch of columns and rows copied and pasted from a spreadsheet (i.e. OpenOffice Calc, Excel or Google Spreadsheets) and imports them into a database.
After pasting the data from the spreadsheet, select the field names from a drop down list and click import. You need to add your own database writing code in order to get it working.
Some validation is included: max number of columns, making sure field names are not duplicated and some basic regexp for the example fields (date of birth and email).
This was made for a ships crew management application we developed here at Greenpeace which we will release soon. It was inspired by something I saw at MailChimp and then by an answer on Stack Overflow by Tatu Ulmanen.
Enjoy and let me know if you have any comments!