Remote home monitoring

iliketrash writes: "I plan to be away from my home for a few weeks in the near future (address not included) and would like to provide a bit of in-home monitoring while I'm away. Presumably I will continue to continue to use it after I return. I would like to be able to perform monitoring from a remote web browser with no special features (Internet cafe or a laptop). I can dedicate an old laptop (OS X, FWIW) to the in-home task. Note that the laptop can run Apache (since Apple provides it with every computer). I would like one or two low-frame-rate cameras or, better, motion-activated cameras. Also, I have an aging air conditioning (cooling) system and given that the daily high temperatures in my area of the U.S. can easily reach 110 degrees Fahrenheit, I would like to be able to monitor indoor temperature. There is a secondary situation where I would like to be able to monitor a particular aspect of part of the AC unit which could be accomplished by a video camera if it responded to heat i.e. infrared. (I understand that IR response is common in some video cameras). I have a home WiFi net that could be useful for connecting to the local computer. Of course, I would like it to be cheap. Are there any inexpensive sensors of these types, preferably WiFi enabled, that can be read by a remote web browser?"