If you haven't been picking these up as they're announced, Amazon decided to finally give you a way to get all 25 with one click over at their 25 Days of Free page (amazon.com) - scroll down past the days to find the checkable list and "Buy selected song" button.
Oh, one more thing - if you're GIFTING MP3s, Amazon says that you can get $2 off with the code GIVEMP3S. Details about THAT over here.
iTunes Top Downloads -- November 21, 2004 Pop - Top 10 SongsPop - Top 10 Albums1. What You Waiting For - Gwen Stefani
2. My Prerogative - Britney Spears
3. Lose My Breath - Destiny's Child
4. 1985 - Bowling for Soup
5. Rumors - Lindsay Lohan