I was looking forward to purchasing the full version of the Spore Creature Creator, so after following the appropriate links, I ended up on the purchase page hosted on GameTree. After pressing the green Buy button, my cart remained empty – no matter which browser, no matter how I reached the page. Better than that – there wasn’t an error message to be seen.
So, I e-mailed the people at GameTree Online asking them to fix the problem. I came back an hour and a half later to see if it was working yet (hope beyond hope that they’d fix it on a weekend), and when I reloaded the page, this was presented to me: 
They have sold out of a digital download.
Let me repeat that – I cannot give them money because they have sold out of a digital download.
Brilliant.
UPDATE: The situation appears to have been corrected. Woohoo! I wonder if they’ll write me back?
UPDATE 2: They wrote me back after the problem was fixed, though the support guy told me that it seems to work now, so I don’t know if they found the problem in parallel to my correspondence or if the techs fixed it behind the scenes and didn’t communicate with their frontline support staff. Either way, I’m having much fun with the Creature Creator.