I understand that many curated trees of life already exist (eg http://tolweb.org/tree/) but is there any website that allows one to input a list of organisms, and then produce the current best guess at their evolutionary relationships?
The best site I managed to find so far is http://itol.embl.de/itol.cgi, which allows you to select specific species from the main tree to plot into a sub-tree, but the tree itself is rather small, so more detailed comparisons cannot be made.