Molly Lewis is a good songwriter
This is a blog entry on Molly Lewis. She's a good songwriter, and plays the ukelele (plus some other instruments). She rose to prominence through an online songwriting contest called "Song Fu", in which songwriters had a week(?) to write, record, and submit a song based on certain criteria: for example, "the song must be exactly 45 seconds long", or "the song must have a chorus of 'It All Makes Sense in the End' ".
Here's a few relevant YouTube videos:
Molly explaining how she ended up with the ukelele
This is a fan-made video for her song "I Pity the Fool", about the wisdom of Mr. T.
This is one of her "Song Fu" compositions, about dating, then breaking up with Wikipedia.
And finally, here's her cover of Lady Gaga's "Poker Face".
There's more: she has a YouTube channel.