If memory serves, there's a saying that goes like:

Two is a coincidence, three it's a pattern.

Apparently, all three mobile operators in Portugal agree that there is no reason to differentiate their service from one another, because all three of them have the following rates for mobile Web access:

• 10MB of web traffic, for 0.99€ per day
• 100MB of web traffic, for 7.5€ per month

All of them! Not a KB more, not a KB less. If this doesn't qualify as cartel, I don't know what does. Then again, maybe they're just plain... never mind. I'm not going to break a promise I made.