Jailbreak tweak lets you customize Notification badges (source--iphonehacks)

Jailbreaking your device allows you to customize almost any aspect of the iOS.
A new jailbreak tweak called Badge Customizer now lets you to change the look and feel of notification badges on app icons.
So if you’re bored of the red badges on the app icons, you can use the tweak to change the color, size and position of the badge.
Under the color options, you can change the color in RGB, change the value of Badge Alpha that allows you to adjust the transparency of the badge and also select the blend mode from a number of options.
You can also change the position of the badge from the default right corner.

After you’ve made the changes, tap on the Preview button by navigating to Settings -> Badge Customizer – > Badge Color -> Preview to get a glimpse of what the badge will look like.
If you’re happy with the changes, tap on the Respring button to apply the changes.
Badge Customizer is available for free on Cydia. You can tap on the download link below if you’re on a jailbroken device to install it from Cydia. You can also check out Boover, which is a free jailbreak tweak that offers similar functionality.