Ruby source code
# Prints number of users across Mastodon instances
require 'open-uri'
require 'nokogiri'
doc=Nokogiri(open('https://instances.mastodon.xyz/').read)
puts doc.css('tr').map { |tr|
td = tr.css('td')[1]
(td && td.text).to_i
}.inject(:+)
@pesterhazy seemed friendlier than just shoving a blob of code in people's timeline