Below is a complete list of all of the working MIT app inventor editor sites
ai2a.appinventor.mit.edu
code.appinventor.mit.edu
ai2.appinventor.mit.edu
ar.appinventor.mit.edu
punya.appinventor.mit.edu
ai2-test.appinventor.mit.edu
code2.appinventor.mit.edu
webemutest.appinventor.mit.edu
datasci.appinventor.mit.edu
iosbuildservertest.appinventor.mit.edu
rtc.appinventor.mit.edu
alexa.appinventor.mit.edu
malden.appinventor.mit.edu -- still up but needs non google login and set password link to email doesn't work