Opera Mobile 10 for Maemo, i.e. for my Nokia N900. Very quickly I found myself using it almost exclusively. It is probably the best application currently available for Maemo 5 platform.
If you've ever used Opera Mobile you are probably familiar with the interface and don't need any introduction. If you haven't, and have a device where you could, then go install it and give it a go. It'll give you much better view of it than I ever could. If you don't own a mobile device that can run Opera Mobile then, sadly, you may as well stop reading now.
So, what's it I like about it? Well, pretty much everything. The familiar interface is as responsive and smooth as ever, and works brilliantly with the touch screen. I don't think I have found any glitches, even with some quite small touch buttons - something I can't say for any other application on my Nokia N900 - at least the ones that do have small to medium size interface elements.
Speed of page rendering is very good, with or without using Opera's caching and pre-compression and rendering system. Bookmarks are seamlessly synchronised across all Opera Mobile enabled devices. Multi-tab interface is a joy to use, and the custom on-screen keyboard is very well implemented, probably even better than the redesigned one in Nokia N900 recent update PR1.2.
The only thing I'd like to see improved, that I've seen to date, is that neither the on-screen nor the physical keyboard respect Maemo system-wide settings for automatic capitalisation of sentences, and word completion. I am sure this can be fixed fairly easily.
So, in summary, if you have a Nokia N900 and browse the Internet on it you need Opera Mobile 10. Go and install it now. It's only your Application Manager away.