My suggestion is to invert your strategy. Instead of telling someone what you are good at, start by asking them what their problems and needs are. Then you can easily steer the conversation to how you can help.

Imagine you're trapped in an elevator with the CEO of your company:

CEO: What department do you work in?

You: I'm a software engineer--but don't hold that against me.

CEO: Heh! Truth is I really value software engineers. [Ed: What else is she going to say?]

You: Of course, but I'm sure you've had your frustrations too. Some of us are better with machines than people.

CEO: You know, one thing that's hard is getting reliable estimates. One week I hear that everything is on track and the next week I'm told we're going to miss our deadlines. It's hard to know the reality.

You: Yeah, I get that. I think there some things with our development process that we could improve. If we had more visibility on the customers that sales is targeting, we might be able to anticipate new requirements. If we had known that we were going to sell to [CUSTOMER X], then we would have worked on [FEATURE A] sooner.

CEO: Interesting! Set up a meeting and we can talk about how to implement something like that.

Obviously, this is just a (lame) example. But the point is that no one cares that you're a polymath in the abstract. They only care about how you can solve a problem that they have.

The more you do this, the more people will remember you as "the person who solved problem X". Eventually you might even be known as the "expert in problem X." And if you end up solving lots of different and unrelated problems, eventually you'll get a reputation as a general problem solver, and people will seek you out.