Something really simple that I need often: invert assignments.
I often have code like this in a initializer somewhere (dialogs most often):
  txtField1.Text = _member1.field1;
  txtField2.Text = _member1.field2;
  txtField3.Text = _member1.field3;
  txtField4.Text = _member1.field4;
  txtField5.Text = _member1.field5;
  txtField6.Text = _member1.field6;
Now I have to write code to do exactly the opposite: assign the .Text contents to the members.
  _member1.field1 = txtField1.Text;
  _member1.field2 = txtField2.Text;
  ...
Would be so fantastic if it was possible to select the code and simply do a "invert assignments".
Could also extend this to comparisms like in 
if(_member1.field.Items.Count == _othermember.contents.total.MaxItems)