Sum of even and odd numbers in Hadoop

I have been reading about Hadoop in the last few weeks. I went through few books and articles, and wanted to try a more hands-on approach. So, while googling for examples I noticed that there is only one real simple example for Hadoop - Word count. This one is pretty easy, but it would not be really interesting to write another article about it. So, my example will be to count the sum of even and odd numbers in a file.

Add fee or discount to order/invoice/creditmemo email messages

In the last few days I have been playing with the functionality of adding another fee to the checkout process. While exploring the topic I stumbled upon a lot of good tutorials for doing exactly that. Namely this, and this one. I read them and followed instructions stated there. With some changes, I managed to recreate the functionality I needed. But, while reading the comments for both articles, I saw the main trouble people had with them. The part about showing the fee or discount in email messages of orders, invoices and credit memos was missing (or not implemented), so here is how i did it.

Change reward message in magento

Reward messages in magento are not coming from database. They are not coming from configuration in admin. They are not set in blocks nor templates. So where are they then?