It depends on the parking service you use. Some allow more than others, but in generaly if what you are thinking of has the word "spam" connected with it, they aren't going to like it. But you should check with them.
What we do is have a lot of blogs and post things to the blogs. In the blogs, we try to find places to put links to our parked domains. So if the post has the word "banking" I might link to a mortgage or credit card domain. If I see "finance" I might link to a my equipment finance domain. My parking service doesn't mind this, because there is nothing special that tells people to click, it's not spam, and when they reach the parked domain it's something that is like what they expect. This is really no different than expired domain traffic, so most services should be ok with it if you ask them. You could also NOT ask them and hope that they just think it's expired traffic, but if they really check they should be able to tell.
The best thing to do is ask them first before you do anything that you are not sure about. They will appreciate that you ask and not just try things first. Remember that the parking services don't just provide us with income, they provide the advertisers with new customers and they need to provide the best traffic they can in order to keep paying us for that traffic. Treat your vendor like your customer and you should do well if they are not jerks...!