All check-ins for Ryanair are done online now. You just turn up at the airport and go straight through customs with your printed boarding pass and passport - that's it. You'll need to print the boarding pass between 15 days and 4 hours before your flight. If you don't, it's £40 at the airport for a re-issue. In fact, Ryanair sends emails in very good time that state VERY CLEARLY that you are required to print your boarding pass. There are no 'hidden charges', just silly people who don't read what's required before they press the final confirmation button and then go on to complain about it.
A few tips for Ryanair.
1. READ THE INSTRUCTIONS. (or get 'overcharged' by the evil Mr O'Leary) 
2. Book ahead for cheap flights. (be aware that each flight may have different prices on different days, so be flexible. You can book a few if you're not sure when you're able to go, though only if they are about a £1 each. There's no requirement to cancel, so no expensive phone calls)
3. Book ahead for no tax and free check-in. (at least two weeks)
4. Take carry-on luggage only. (checked luggage costs £10)
5. Use an 'Electron' card. (no process charge)
6. Don't buy 'priority boarding'. (there is no 'free for all', just use rear door)
7. Don't buy Ryanair insurance. (you should have some anyway)
Happy travels! I've had no problems yet. 
edit: would just like to add that Ryanair has the best reliability record over all other airlines - though there was a 10 minute delay before flying out of Marrakesh on my £5 ticket - but I got over it. 
[ Edit: Edited on 26-Jul-2009, at 09:57 by fabyomama ]