I use Visual FoxPro's editor. I've never had a problem with huge files in it, so I haven't went looking for anything else.

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>>Programmer's File Editor (www.lancs.ac.uk/people/cpaap/pfe) - NotePad substitute. Main advantages: 1) overcomes the file size limit, 2) MDI (multiple documents in a simple "task").
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>I use EditPad Lite from http://www.editpadpro.com/editpadlite.html
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