Is there a way I can automatically scan my source code for methods that are over (eg) 300 lines long so that they can be flagged for review (with an aim to refactoring to smaller methods)
I expect any such tool may be language independant, but ideally I'd like to run this over c# code.
Why dont you use some code counter tools which you can search in google for. http://www.google.com/search?hl=en&source=hp&q=code+counter+tools&aq=f&aqi=&aql=&oq=&gs_rfai=
Is there anything specific you are looking for. Why stopping with 300. Are you developing some contest where you would like to restrict people from writing more than 300 lines of code. Anyway be more clear so that we can help you.
I use this one and i find it very useful.