Full of something:
* Beautiful
* Careful
* Cheerful
* Doubtful
* Fearful
* Hopeful
* Joyful
* Painful
* Powerful
* Successful
* Wonderful
Capable of something:
* Playful
* Harmful
* Helpful
* Thankful
* Thoughtful
* Truthful
* Useful
* Wasteful
* Wonderful
Other:
* Awful
* Beautiful
* Faithful
* Handful
* Mouthful
* Shameful
* Skillful
* Wonderful
Some less common examples:
* Boastful
* Dutiful
* Hateful
* Hopeful
* Meaningful
* Peaceable
* Restful
* Trustful
This list is by no means exhaustive, but it provides a good starting point for exploring words ending in "-ful".