This app has been released: https://portableapps.com/apps/accessibility/nvda-portable
Licence: Open Source (source code)
Description: (from website) NonVisual Desktop Access (NVDA) is a free and open source screen reader for the Microsoft Windows operating system. Providing feedback via synthetic speech and Braille, it enables blind or vision impaired people to access computers running Windows for no more cost than a sighted person. Major features include support for over 35 languages and the ability to run entirely from a USB drive with no installation.
Download NVDA Portable 2014.3 Development Test 1 [16.6MB download / 71.1MB installed]
2014.3 Development Test 1 (2014-10-24):
- Base app updated
2012.3.1 Development Test 1 (2013-04-24): Initial release
Please Note: NVDA Portable is still affected by the issues described here. As such it can't be considered 100% portable, but it is here for those who want it.
I am not so great at keeping it up to date, but if you drop me a message (here in this thread, or any of the ways to contact me via my website are also good) then I will update to the latest official, stable releases (no rc versions) as soon as I can.