Assuming we're talking base malts only, right?
Crisp MO
Weyermann floor-malted Bo Pils or Best Malz Pilsner
Continental light Munich (I haven't tried a brand comparison yet, since most of the online shops don't give you an option)
Unless someone out there brews a lot of Vienna lagers or wheat beer, I'm guessing that a whole lot of us will have fairly similar lists. I'll be interested to hear everyone's brand preferences, though, since there are still a lot of brands of malt out there that I haven't tried.