TransparentLocker is a lockscreen with transparent gradient background and slider unlock style (as in Android 2.1).
It uses overlay window, that blocks all user's activity until slider moved to unlock.
Also user can toggle ring sound mode by sound slider.
There are many settings for different phones.
When new sms or missed calls appears, locker shows sliders, that opens system apps.
User may to set window type and window flags of locker manually.

Compatibility: Android 1.5+
Supported languages: English, Russian

This is beta version, not fully tested, but seems to be usable

Screenshots: