Don't own any, but just find them to be uniquely interesting animals for their odd behaviors and habits (such as why many birds end up pairing together for a number of years to raise offspring while most other animals do not), which I end up finding to be similar to many of the quirks that us humans also tend to share at times.
My family did have a budgie (parakeet) though when I was younger, but it was not my pet specifically and I didn't take a huge interest at the time.
I jump from topic to topic a lot, hyper focusing on it to suck up whatever useful information I can. History, programming, art, music, whatever. Just like many of us here, I just have a curious nature about nearly everything and want to find out what makes something do or act as it does :)
Since I started to take more interest in them, I realized how much more they happen to be around while running errands or just getting some exercise at the park. I guess if anything, they make me feel closer to nature when I'm surrounded by concrete and skyscrapers. Sort of an oasis in the middle of a desert if there's a metaphor for it.
Even the lowly house sparrow is more savvy than I used to believe. They've been observed making use automatic opening doors by triggering the sensors (http://elibrary.unm.edu/sora/Wilson/v103n04/p0725-p0726.pdf). After I read that, it made more sense how the sparrows at a nearby supermarket by me happen to find shelter inside its walls.
For anyone that just has a general interest or wants an informative introduction to birds, the BBC did a great series on them a while ago, narrated by David Attenborough (http://en.wikipedia.org/wiki/The_Life_of_Birds). Can't say I like all birds, but I think they're a species that tends to be underestimated and taken for granted by us when compared to mammals for their intelligence and adaptability.
Birds and Squirrels are the easiest to do backyard "research" on/with. We did an experiment with jays where we put some nuts on a button which was a door bell, it would ding when they too k the nuts. Then we'd go out and set up an experiment on the porch. After about a week of this they'd ring the button when they wanted to be "experimented" with :-) One of the things I wondered was how much energy you could harvest from a squirrel. Basically training it to run in a wheel until the treat dropped. (the wheel being hooked to a generator to charge a battery). Then stretching out the treat drop until you reach the end of squirrel's patience.
