When my first child was on her way I bought a fancy baby monitor. It had pan, tilt, zoom, night vision, a temperature sensor, etc etc. It did everything. It had two huge problems though: it severely degraded my wifi whenever it was on and the battery in the monitor went bad before the second baby arrived. Lame.
For my second child I switched to using an old Android. It doesn’t pan or tilt. It doesn’t have night vision. But it works, it is free, and it uses junk I already had laying around.
On the old Android I use IP Webcam. It is a free app that streams your phone’s video/audio.
On my current phone I use VLC for Android beta. It is also free, and lets me stream the audio from IP Webcam (which is all I want at night anyway). I leave it going all night so I can hear my son in case he gets up. It also makes it easy to go out and do yard work without worrying about him waking up without anyone inside to hear him.
To stream the audio on VLC, use the IP from your IP Webcam phone and add audio.wav to the end, like this: http://192.168.1.133:8080/audio.wav
During the day, when I’m in my home office working, I can use my browser to watch/listen to him when he is down for a nap. Again, I can’t pan or tilt, but all I really care about is whether he is awake or asleep. I don’t really need pan/tilt for that.