html entities decode
("I'll "walk" the <b>dog</b> now" => "I'll "walk" the <b>dog</b> now")

php array to json
("array('q' => 'asd')" => "{"q": "asd"}")

base64 decode
("" => "")

email mime decode
("=?UTF-8?B?0L3QsCDQstGB0YLRgNC10YfRgy4uLg==?=" => "на встречу...")

email headers decode
("header_name: =?UTF-8?B?0L3QsCDQstGB0YLRgNC10YfRgy4uLg==?=" => "header_name: на встречу...")

quote-printable decode from email
("=D0=90=D0=BB=D0=B5=D0=BA=D1=81=D0=B5=D0=B9" => "Алексей")