I see no development of the dude. Is it really still alive?
They do a little bit from time to time, everyone hopes they will do much more or make it open source which I doubt they will do.
As it stands it is the only network monitor of it’s kind. There are a few bugs and annoyances but it works fine. The worst part is false positives which I believe are mainly in windows installations. There are some real gotchas though, the database will stop working somewhere just above 2gb and you would have to start over. SNMP can run the CPU up on your routers and switches so be careful with auto discovery, I don’t use it. Also disable the reading of the BGP table on any routers that are connected to the internet. With all that said you can make it monitor damn near anything. Getting started is easy and only takes a few minutes but it will take quite a bit of work to really understand how functions and probes are built(if you want to). The biggest limiting factor is the lack of any user variables to use in the probes but I have been able to get everything I have wanted without them…YMMV.
About every probe you could want has been added to the probe thread and there is good detail on the wiki to help get started and build your own probes. I recommend that you read the quick start guide and search the probe thread and the how to build a good probe wiki if you can’t find what your looking for. So although it could be a lot better it already does tons of stuff and it really is a great program. One of my favorite features is the windowing system, all windows are above the main window but they are not locked focus so you can work in any window and have many windows up at a time when you are configuring it.
There is also a post of dude alternatives which lists some of the other systems out there if the dude is not for you…