Kroc

//safeTransliterate v3, copyright (cc-by 3.0) Kroc Camen <camendesign.com>
//generate a safe (a-z0-9_) string, for use as filenames or URLs, from an arbitrary string
function safeTransliterate ($text) {
	//if available, this function uses PHP5.4's transliterate, which is capable of converting arabic, hebrew, greek,
	//chinese, japanese and more into ASCII! however, we use our manual (and crude) fallback *first* instead because
	//we will take the liberty of transliterating some things into more readable ASCII-friendly forms,
	//e.g. "100℃" > "100degc" instead of "100oc"
	
	/* manual transliteration list:
	   -------------------------------------------------------------------------------------------------------------- */