Cydia
You can try beta versions of my software on my Cydia beta repo. Just add [Address to be released soon] to your sources in Cydia.
HTC Plugin for Lockinfo (Native)
This plugin displays an HTC Sense style clock with weather and calendar in LockInfo on iOS devices. Currently all iOS versions 3.X plus should be supported.
I am currently working on major upgrades to this plugin and they will hopefully be ready soon.
The plugin is available on the ModMyi repo.
CustomPrefsBundleKit
I am also working on a framework for jailbreak developers to incorporate custom settings into the Settings app (via PreferenceLoader) with much more flexibility and customisability than Preferences.app (Settings) allows. This should be ready soon!