Having used an iBook running OSX for a week,one application on it that utterly blew me away was QuickSilver, which is a launcher with a PhD? in data mining and an MA in Zen aesthetics. Jealous and envious, I wanted something similar for windows. Alas nothing exists like QuickSilver, so I looked to see what the best Launcher there was for windows. My criteria were:
After googling around, I found AppRocket, which was OK (very clean UI and simple, but large memory footprint) but left me unsatisfied. I also tried True Launch Bar, which is excellent but still menu-based thus slow, also requiring full manual configuration.
Luckily by chance I then discovered Find and Run Robot (FARR), a piece of excellent Freeware. It fulfilled all my criteria and more! You simply select a set of folders to scan, and optinally configure rules to weight (higher scores) entries based on your preferences. It learns from your selections during use so you most used entries get bigger scores.
Additionally, the developer loves to receive feedback, discuss suggestions for improvement and actively implement them; and the forums are very friendly. If no one has ever used a launch tool before, they will be shocked how more productive they will be than fighting with the Start Menu & Explorer! Of course it works perfectly with Opera:
Main FARR web page
The FARR forum
The screenshot shows it in action, I pressed <pause> to activate then started typing Opera, it has progressive searched through my folders to find the most relevant items, the ones I use most are given greater weighting (score) so are at the top. Faster than any other way to launch files/searches...

The software needs no "install"; the installer EXE can be opened as a ZIP file and contents extracted manually if you prefer, which is great for those of us who prefer manual installation…