If you set up your VPS with a hierarchical deterministic wallet[1] or a passphrase-protected private key[2], your hosting provider will be unable to determine your private key.
There are issues to be aware of, but for small amounts it's perfectly reasonable to acknowledge a transaction without confirmations (this is known as a "zero-confirmation" transaction).
For example, our service[1] clears transactions in seconds.
Obviously, the security and scalability of our platform is a big part of the value we provide to buyers and sellers.
For now, know that there are a number of measures we take to ensure that the site and users' bitcoins are secure: The site runs entirely over SSL (HTTPS). We protect against CSRF and XSS attacks. The addresses used for purchases are generated offline. Withdrawals are handled separately from the application server. Importantly, sellers can withdraw their balances quickly to the Bitcoin address of their choice. As we scale up, we'll store the majority of sellers' funds offline, keeping enough for transaction fees and withdrawals.
We built Yumcoin because we think existing solutions for accepting Bitcoin are too complicated. A few people have to built custom sites to accept Bitcoin for their products (eg. Knife Party, James Altucher), but we think the process can be a lot simpler. We host your product, give you a short link you can share with your audience, and manage the Bitcoin payments for you.
There's lots of new features we're working on, but it's already useful and fun.
There's no catalog yet, and you only need an account to sell products. Buying a product is easy and does not require an account. You just need some Bitcoin... here's an example: https://yumcoin.com/p/osZO
Thanks! The product preview is optional, but it makes the page look better and can help to sell the product.
The preview media link is provided by the seller in addition to their product's file. For example, it could be a YouTube link to the trailer for an independent film, or a SoundCloud link to the preview for a full album.
Glad you think it's cool! We have big plans for launching online stores and catalogs through the site, but this is the "MVP". Right now we're focused on making it fast and easy for creators to share products with their audience and accept Bitcoin.
[1]: https://github.com/bitcoin/bips/blob/master/bip-0032.mediawi...
[2]: https://github.com/bitcoin/bips/blob/master/bip-0038.mediawi...