This forum was created by the founder of physicsgre.com. Steadily, there is idea to create from this forum the web-resource, similar to that of physics students. At least this year the idea is to make list similar to http://www.physicsgre.com/results.php
if people on this forum help to contribute to it. I myself haven't seen any resource better than this forum for the math subject preparation.
As for #26 in 8767, every point (0, k), where k is in [-1,1] will be the limit point of the set sin(1/x). Therefore, to make it disconnected, we need to move k "outside" this interval.