Is there a way for Flex / AIR to receive syslog notices from devices such as cisco switches etc? Does anyone know of any information I can read or sites to look at?
If you are talking about calling native methods, flex/air cannot do that. But there is an opensource AIR-Java bridge namely merapi that lets you connect your AIR app with java code. I guess java should be able to do what you are looking for.
AIR apps can read local files. In the case of receiving syslog notices from cisco switches or other devices, I used to set them up on the receiving machine to be added to the local syslog there to have everything in one place (we're not talking windows here :-)). Using mtail and grep I had a few consoles open that showed me what was coming in.
If you write an Actionscript parser to read your local syslog - using bytearray like described here - then it should be possible to read through the whole file and note the interesting bits (I haven't done this myself, so no guarantees!)
If it more a question of getting real time data from devices, I would look into snmp (but you will probably need to write additional stuff in php or python to query the devices for you).