What is your favorite invention of the 21st century (2000 onwards)?

Your invention must have been invented in the year 2000 or later.

Suggestions include but are not limited to:

- PlayStation 2 (2000)
- Bluetooth (2000)
- iPod (2001)
- Original Xbox (2001)
- Nintendo GameCube (2001)
- Reddit (2002)
- Firefox (2002)
- iTunes Store (2003)
- FaceBook (2004)
- Twitter (2005)
- Xbox 360 (2005)
- Nintendo Wii (2006)
- PlayStation 3 (2006)
- iPhone (2007)
- Kindle (2007)
- Hulu.com (2008)
- Controller Free Gaming (2009)
- iPad (2010)
- PrintBush (2011)

The internal combustion engine. I bought one of these and it fits inside the "car" I've owned for a few years now (pre-engine, it was just sitting there doing nothing). It's great. Much better than trains and taxis.

Vantablack

I think the fidget spinner is probably one of the most original inventions. It will define its decade.

Applications of the CRISPR/Cas9 system for genome editing.

Nothing good has been invented since Vistavision.

Noise-cancelling headphones

- iPhone (2007)

Amazon Echo