I've been exploited in the past, but less and less as time grows on. When I changed to Wellbutrin there was a huge change - I've become way more intense and assertive. I've been told by friends that I'm actually a bit scary.
The wierd thing is, I still don't handle direct conflict very well, I just get overwhelmed and flustered, and just have to leave when I get too upset or risk having a melt down on the spot.
However, I still very often get my way, mostly through appealing to others to do my negotiation for me and blatent documentation.
What I mean by blatent documentation is creating a record of any exchanges that I feel that I may be exploited in a way that's obvious to the other person. So, in Fnord's case, I'd do stuff like carrying around a dictaphone all day, and recording little reminders for myself about stuff, including quick summaries of the details of work related discussions; the important thing is to do this about everything, so they can't accuse you of targeting them, but also to do the quick summaries of the conversation in an obvious manner so they can't miss that it has been documented. The next time someone steals your idea, go to someone else all concerned and say that you think that So-and-so may have used your idea and forgotten to credit you, and show them the person's report and the record of your conversation. If they agree, go on about how you're sure that it's an honest mistake, but you're a bit afraid to confront them, could you come with me? Then when I confront So-and-so, I act very concerned and hurt. The guilt plus the evidence plus the witness pretty much makes him cave, at which point I start insisting that he write a quick email to the boss to clarify the matter.
If you do this right, no one even gets angry at you. And if you do it often enough, ppl start respecting you - it's awesome. I love my Wellbutrin, even if it makes me pychotically passive aggressive