Etch

Makes good use of responsive design – try narrowing your browser window. 

Si Digital

Includes unobtrusive animation and some lovely fade-in effects for text.

Neotokio

This currently has a gorgeous, innovative ‘out of office’ skin on it, as well as some great touches on its website.

Clearleft

Avoids scrolling for the sake of it, and focuses on usability.

8 Bis

What’s not to like about the way the label changes colour as you hover from image to image?

Carnation

This one is a scrollfest, with lots of excellent micro UX effects (try hovering over the red logo, or the social icons).

Red

A focus on strong typography and speed makes for a lovely user experience.  

KathArt Interactive

The tour is certainly novel, but it takes an age to load, and the navigation goes AWOL.

Leeroy

Some slick slide transitions, but I’m not convinced that the image-heavy team page works.

The Twelve

I like the attention to detail on those thumbnail hover states, and there is some smooth animation if you’re prepared to wait for it.

Handsome

A site that seems to have been created with the swipe in mind. 

Teehan & Lax

I’m such a fan of this site, especially its wonderful ‘story’ page.

Buffalo

Another admirably clean HTML5 experience. Check out its Project Planner form.

Poke

A content-focused site, rather than the bells and whistles approach adopted by many agencies, though infinite scroll means that you end up chasing the footer down the page.

Seen any other notable HTML5 sites recently? By all means share them in the comments area below.