Am Mobile

Download link for free application .
Forgot to lock your phone's keypad? AutoLock locks it automatically after configured time period. Simple and free. Autolock is an automatic key lock application for S60.

AutoLock is available for all Nokia S60 Symbian phones.
Compatible with:

Nokia: 7650, 3230, 3650, 3660, 6600, 6620, 6630, 6670, 6680, 6681, 6682, 7610, N-Gage™
Nokia NSeries: N70
Siemens: SX1

AutoLock v1.1 for S60 3rd edition phones
Compatible with:

Nokia: 6120, 6121, 6210, 6220
Nokia ESeries: E50, E51, E60, E61, E61i, E70, E90
Nokia NSeries: N73, N77, N82

Sync your S60 3rd edition calendar with Google Calendar
CalSyncS60 provides two-way synchronization between Nokia S60 phone and Google Calendar.
For example, when you add an appointment to Google Calendar it will appear also in your phone calendar.
Just start the application and hit sync.
Download CalSyncS60 0.3.3 BETA
All Nokia S60 3rd edition phones are supported. See devices here
Features:

Bi-directional synchronization
Scheduled automatic sync (Currently if turned on, syncs every 2 hours)
Supports standard appointments, all-day events, alerts and recurring events
Fast sync - only changes are transferred over the network
Completely free!

Zip and unzip files in your S60 2nd edition Symbian device.
S60Zip is a free ZIP file manager for Nokia S60 2nd edition. It's PKZIP compatible and capable to compress and uncompress archives in device.
You can e.g. download ZIP file via browser and it's automatically launched to S60Zip. Then you can extract whole content into phone or open single items straight without extracting them.
Features:

PKZIP compatible.
Compress/uncompress.
Open ZIP files from messages (e-mail, Bluetooth), browsers, file explorers etc.
Send ZIP files via Bluetooth or e-mail.

S60Zip v1.02 supports all S60 2nd edition phones.
For S60 3rd edition, check Y-Browser with ZIP plugin.