I found a quick way of doing “View Source” in Konqueror. The built-in way opens your text editor, which isn't instant in my case (I have it configured to use Kate, which is great if I'm actually going to edit something, but usually I just want a quick peek, and I want it to be instant).
The trick is to use the following bookmarklet:
javascript:void (function(){c=unescape(document.documentElement.innerHTML);
c=c.replace(/&/g,'&'); c=c.replace(/</g,'<');
c=c.replace(/>/g,'>');
x=window.open('');x.document.write('<html><head><title>Source of
Page<\/title><\/head><body bgcolor=\'#ffffcc\'><pre>' + c +
'\n<\/pre><\/body><\/html>');x.document.close();return false;})();
You can use bookmarklets in Konqueror via 'Minitools' – it's quick and convenient, but so badly documented that I only just found out about it. The page's source is opened in a new window.