A little python script for notepad++. This searches through a WordPress xml export file and converts date strings to unix timestamps. Very useful when using wp-types for custom date fields. Requires the notepad++ python plugin..

wp_xml_replacer.py

import time
import datetime

editor.beginUndoAction()

def calculate(match):
	epoch = datetime.datetime(1970, 1, 1)
	s = "%s/%s/%s" % (match.group(1), match.group(2), match.group(3))
	t = datetime.datetime.strptime(s, "%Y/%m/%d")
	diff = t-epoch
	i = int(diff.total_seconds())
	utimes = str(i)
	return '[' + utimes + ']'

editor.rereplace('\[([0-9]+)/+([0-9]+)/+([0-9]+)\]', calculate)

editor.endUndoAction()