I've often thought the same.

This should be easy as a greasemonkey script to save other people having to make changes to support it.

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EDIT: Out of curiosity I made up a javascript bookmarklet that seems to do the trick... upsize all the page's upvotes to 30x30

  javascript:{im=document.images;iml=im.length;for(i=0;i<iml;i++) {if(im[i].src=="http://ycombinator.com/images/grayarrow.gif"){im[i].width="30";im[i].height="30" } } alert("Done"); void(null);}

Cut and paste that into your browser URL bar, or bookmark etc. It's easy to validate by eye, for the worried