LogFusion is an easy-to-use tool which allows you to monitor your Windows event logs in real time.
If your PC is currently unstable, for instance, you might use the program to open and display the System event log. One further click will set the LogFusion window to stay above any other applications. Then just leave it in the corner of your screen, and you'll be able to see any Windows events as they happen.
LogFusion isn't restricted to event logs, though. It can load and display just about any text logs, from any application. So if you're currently monitoring what a particular program is doing by manually opening a text file in Notepad - and then reopening it, every few minutes - then you can probably save yourself a great deal of hassle by using LogFusion, instead.
Binary Fortress Software also produce a commercial version of LogFusion with some very handy extra features. Text filtering allows you to search for particular events, for instance; you can have the program highlight rows based on text or regular expression matches; it can watch folders and automatically and add news logs as they appear; and a tabbed interface allows you to have multiple logs open at the same time. All this can be yours for a $9 lifetime licence, and you can find out more on the LogFusion site.
A very easy way to monitor Windows events as they happen