4chandownloader/4c

#!/usr/bin/python

import re, urllib2

regex = 'href="(\/\/images\.4chan\.org\/b\/src\/[0-9]+\.jpg)"'
url = 'http://boards.4chan.org/b/res/400860795'

page = urllib2.urlopen(url).read()

search = re.compile(regex)
matches = search.finditer(page)

urls = []

for match in matches:
	if match.group(1) not in urls:
		urls.append(match.group(1))

print urls