I don’t think asking what the “best” samples are for portfolios is the best way to go about this. People have different opinions on that. And secondly, it probably won’t fit the client so it’s best for you to come up with your own solution regarding UI.
As for web technology, I would say HTML5 would be your solution. But obviously that’s just for markup. For functionality, you would need to describe what you would like to accomplish.
With saying that, you could try looking at http://awwwards.com to get an idea but also remember that inspiration lives outside of the web as well.