I suck at daily blogging.
17. Blogging (did you really not see this coming?)
Both creating and consuming. It's nice to see what's going on out there, what other people are doing, and to share your ideas and achievements yourself.
18. Tabbed browsing
Despite its attendant, the Wikipedia tab plague. It seems like such an obvious thing I'm amazed it took so long to come to fruition, although it probably only feels recent to me.
19. Super-easy free open-source software development
I am thinking in particular of Arduino, Python, and Processing (which I have yet to play with). Between the fact that these can be freely downloaded and used by anyone for anything and the massive culture of sharing tricks, tips, and how-to docs, you can pretty much figure out how to make a computer (either a PC or an embedded system) do what you want, quickly and easily. And cheaply.