Astroburn Audio (free) is a simple, good-looking, and effective CD audio burning app. It's very easy to use and supports a fair number of audio formats. Still, this one-trick pony leaves me wishing for just a bit more.
As you can tell from the screenshot, Astroburn Audio is nothing if not pretty. It's also efficient, with all options accessible from the main screen. You can add files via drag and drop, or open an Add files dialog. There's an erase disc function for those greener souls that use CD-RW, as well as transport controls for playing back songs.
What's missing are a few basics and niceties. For instance, there's no way to see the info on the files you're burning. I use several different encodings (and names) of the same song for my compatibility tests, so having Astroburn Audio display only the identical tags was frustrating. This made me long for a tag editor, which would've allowed me to fix my mistake.
Astroburn Audio transcodes most Windows media types as well as the APE and FLAC files that only a few programs support. However, it doesn't support Apple AAC or lossless, OGG, or any WAV files beyond your standard 16-bit/44kHz type. Additionally, my system slowed to a crawl while it was enumerating the disc in the burner. That experience lasted only ten seconds or so, but it was a bit disconcerting. On the other hand, it burned discs just fine with a minimum of interference during the actual write process.
Here's hoping the folks at Astroburn will read this and improve format support, display more file information, and perhaps add that tag editor. I'm rooting for it because what's there already is extremely well-designed. Even as it stands, it's well worth a look.