Jason, who runs Yoyo Market, contacted me to let me know about their service and thought it might be a good resource to share with the readers of Surviving in Japan. I wasn't sure how different it would be from the other stores, but from talking with Jason and checking out their site, I can see that even with similarities, it stands apart in its own way.
What do they do?
"Yoyo Market brings you the finest goods from IKEA and Costco straight to your door anywhere in Japan. On top of that we also carry a large selection of imported foods and organic goods from importers across Japan. We are the only IKEA home delivery service in English in Japan."
For anyone who may not know, Ikea Japan doesn't offer online shopping, so you have to live near one of the locations in Japan or travel to one and have items shipped to you otherwise.
Or if you have something else in mind you need help getting (Jason mentioned a Baskin Robbins ice cream cake, as an example), they can help you with that too.
They don't charge extra for cool or frozen shipping. It's a flat rate of 950 yen - anywhere in Japan. If you spend over 30,000 yen, shipping is free. If you live on Honshu or Shikoku and you order before noon on a weekday, your order will arrive next day, and if Hokkaido, Kyushu, Okinawa, etc., 2 days. (Though if you order on the weekend, they won't ship until Monday.)
I ordered from Yoyo Market myself to try them out (no special discounts or anything like that for me, no worries), and I was impressed with the types of products they have on their site (these products can also be found elsewhere too, of course, but it's nice to see the variety all in one place), the prices of the products, and the very fast and cheap shipping.
One difference from the other two is that they don't offer the personal import option The Flying Pig has in regards to selling Costco food imported from overseas Costco stores, nor do they have the selection of FBC's general store (as FBC imports from abroad). However, Jason mentioned they are constantly expanding their product lineup, so this will likely continue to change in the future.
If you have questions or want to check out more, feel free to visit their website, or contact them if you need help finding something.