Excellent post, wil.

I can relate well to your experiences, as I have been there, and continue to do so periodically as I move around (occupational hazard of being a consultant).

However, there are a few traps for the unwary, and I will use this thread as an opportunity to share my experience.

Hardware adept

If you get a reputation for being a dab hand with a screwdriver (or even a soldering iron), this may be best to keep to yourself. You are likely to find that the company will refuse to spend money on new hardware or maintenance, as they have an expert on site. This also equally applies to MS office applications etc.

Being too helpful

Although having a helpful and respectful attitude to users is an asset, make sure that they are being reasonable, and are not wasting your time. If they have a repeat of a problem which was solved, you can rightly say that you have already given them a solution. However, there may be an underlying issue with why the problem has reoccurred, but if this is the case, discuss with your management and earn ++ points for spotting it.

Not passing on information

Although it seems on the surface a good career move to set out to try and make yourself indispensable. In practice, the reverse is usually true. If you have set yourself up as the standard repository of all knowledge and wisdom about XYZ, you might find that you have a rival who is more forthcoming with information, who has ousted your position on the team.

Closing your ears and eyes to what is happening

At all times, try to be aware of the politics and dynamics of your department. It is easy as a good programmer to get a reputation as a quiet person who gets on with the job. The danger here is that you are excluded from important design decisions, juicy new projects, and news about the future of the company (and hence your future). The answer to this one is to ask questions (why do we do that?) and be proactive.

General points

Go check out Dilbert, but don't take it too seriously. Although Scott Adams has a somewhat jaundiced and cynical view of corporate culture, the humour content is second to none. Also there are many useful techniques for recognising and dealing with pointy haired bosses.