Looking at the matlab help for anonymous functions looking at section functions with multiple inputs or outputs, I would think that you would be able to do something like the code below
Second edit Turns out if you use deal (as given by thewaywewalk) or if you dereference the anonymous function you can get the same thing.
crazyfunction=@(a,b) {(a^2),(b/2)};
[x y]=crazyfunction(a,b);
Quick and dirty test shows that this will give no syntax errors
>> f = @(x,y) {x^2, y/2};
>> f(2,2)
ans =
[4] [1]
EDIT Fired up matlab to see my original answer would actually work, doesn't look like it (see second edit you need to use {}).
You would either daisy chain two anonymous functions together in such a way that a and b are part of anonymous function c or use a struct of anonymous functions effectively as shown below
crazyfunction={@(a) (a^2); @(b) (b/2);}
[crazyfunction{1](7) crazyfunction{2}(9)]
ans =
49.0000 4.5