regex file names from path and/or url

I need to extract filenames so I can transact across many logs of different types and such.

some logs have full urls - http://www.test1.com/43/test.txt

some logs have only paths - /43/test.txt

some logs are standar looking logs and some are actually XML data dump that was indexed as a "standard log". - <url>http://www.test1.com/43/test.txt</url>

sometimes the whole path may be enclosed in parenthesis or quotes too - "/43/test.txt"

the basic principle is i need to extract files (filename.ext)

I don't have access to the file system and can only use "Extract Fields" in the web interface?

any thoughts?