If you work much, you want a high display resolution. However, the laptop still has to be small, so there will be a compromise. Personally, I would go for something like 1280*768 on 13", which is both small and possible to work with.
The other thing you really want is silence. And battery life.
Even if you code a lot, CPU speed is rather irrelevant. Any Core2Duo will do (dual core and 64Bit are great to have). But RAM, you can't have enough -- and since it is cheap at the moment, don't bother and directly upgrade to 4G.
For me, this is a MacBook, but there are plenty of alternatives. For example, the FSC Lifebook series is really great.
If possible, look for those business-offerings. They tend to use a little older but more reliable hardware, which can really save your day and will most certainly enable you to run linux.
The other thing you really want is silence. And battery life.
Even if you code a lot, CPU speed is rather irrelevant. Any Core2Duo will do (dual core and 64Bit are great to have). But RAM, you can't have enough -- and since it is cheap at the moment, don't bother and directly upgrade to 4G.
For me, this is a MacBook, but there are plenty of alternatives. For example, the FSC Lifebook series is really great. If possible, look for those business-offerings. They tend to use a little older but more reliable hardware, which can really save your day and will most certainly enable you to run linux.