gnokii is a freeware software for Linux, Solaris and BSD based computers that allows you to manage your Nokia S60 2nd Edition mobile devices like 3650,6600, etc over a serial, infrared, bluetooth or USB connection.

Features include:

SMS
You can send SMS, receive them and save them in the phone. gnokii supports delivery reports, picture messages (Nokia own protocol), concatenated messages, wap pushes, unicode messsages. gnokii allows you to send and receive logos and ringtones over SMS.

Phonebook
gnokii offers you possibility to read and write phonebook. Phonebook entries can be displayed in human readable form or can be exported to comma separated output, vCard version 3.0 format or ldif format. You can import data from the same formats. Please note, that supported phonebook entries depend on the phone features and therefore may not be all imported.

Calendar
gnokii supports either calendar or todo lists. gnokii is capable to export calendar to iCal files and import them from the same format. Most calendar features like different types of events, recurrence, start and end times are supported.

Call management
You can initiate and answer calls with gnokii.