NoSpam is a simple, no fuss addon which filters whispers from level one characters and does not show them.
Currently broken you should disable the addon until it is fixed.
Additional filters maybe implemented in the future if enough interest is shown.
Apparently UnitLevel() returns 0 for level 1 characters and I did not notice this until further testing. NoSpam has been updated to reflect this. Sorry if people got spammed by level ones!
Currently broken, going to research more into fixing the problem, expect another update very soon.