Have you noticed the Daily UI Pens popping up in the Picks lately? They're inspired by Daily UI, an email-a-day challenge for designers to create UI elements — landing pages, forms of all kinds, 404 pages, and a whole lot more.

I first noticed these popping up in Recent Pens near the end of last year, but they're really picking up steam now. Check out a few of my favorites!

Fabio Ottaviani is up to day 22 as I write this. He's turning out gems like this slick credit card checkout form.

See the Pen Daily UI #002: Credit Card Checkout by Fabio Ottaviani (@supah) on CodePen.

I'm fond of fun 404 pages (I love to collect them), so naturally I like Dominic Magnifico's 404 page for the truly Lost.

See the Pen Daily UI #008: 404 by Dominic Magnifico (@magnificode) on CodePen.

Maybe if my inbox had Pavel Laptev's delightfully animated app icon, I wouldn't feel so bad that I can never get it down to zero.

See the Pen Daily UI #005 App icon by Pavel Laptev (@PavelLaptev) on CodePen.

No one can be uncheered with a balloon, so of course I have to smile when I see Star St.Germain's charming landing page 🎈

See the Pen Daily UI 003 - Landing Page by Star St.Germain (@thisisstar) on CodePen.

Check out the dailyui tag for even more!