Y Gweiadur - the on-line dictionary has re-opened its registration for new users.
If you have read the posts about additional learning resources, you may have come across mentions of y Gweiadur, a very good on-line dictionary available here.
It has been closed to new registrations recently while they make some improvements. I have just seen a note from them saying that they are temporarily re-opening registrations, so now is a good time to register to use it. Registration is free.
A thumbs-up from me as well, for what it's worth :)
Go and register if you haven't already done so!