*edit* much improved windows performance. Well done, vb!
A nice lightweight way of doing things (I wrote up a whole theme to do something similar, with more effects - http://userstyles.org/styles/6292 - but it's huge, and requires constant bugfix edits). Very cleverly done! Does strange things to the locationbar and searchbar (the black line isn't entry text but an artifact) on vista 120dpi: http://img149.imageshack.us/img149/3226/31324769em3.png
Do me a favor and take a look at my theme and post a sshot from 'nix so I can try to work out glitches; feel free to take a look at my code and steal to your heart's content (with credit given of course; let me know if you'd like more prominent credit for snatching your rounded borders idea to remake my own theme): http://userstyles.org/styles/6601
Try this code for the URLbar on 'nix; it fixes the weird glitchy appearance on 'doz, but donno what it'll do on 'nix: #urlbar > dropmarker.autocomplete-history-dropmarker { margin-left:-5px !important; /*pull other elements closer*/ -moz-border-radius: 8pt !important; border:none !important;}
About WellRounded 3 on May 08 2008
About tooltip transparent on Apr 29 2008
About DOM Inspector - reduce indent on DOM tree on Apr 20 2008