I like how AltGr+7/8/9/0 gives me { [ ] }, it's a very nice grouping. The key next to Z is < > and you get | with AltGr, which is very handy.
Only thing that's mildy annoying from programming viewpoint is that for tilde and backtick, the keys do diacritics - you need to press the diacritic key and space. Backtick is especially fun, because it's shift+acute, space. Meanwhile, the key next to 1 does § ½, which aren't that handy most of the time. I often just stick backtick on that key if I'm particularly assed to customise keyboard keyouts. Similarly, shift+4 is ¤, which is another not a particularly useful character (but I don't mind that, because £ $ € all need to be produced with AltGr, which is at least consistent).