Loading data--but not LoadVars or XML

Hi all. Does anyone know if there’s a class or object that allows you to read in “raw” data, so you could write your own parser?
LoadVars seems too restrictive, but XML has more structure than is necessary–I’d love to be able to just read in lines from a txt file.
If I used LoadVars, how could I separate lines into an array by parsing linebreaks?

Thanks in advance!