I believe this mainly depends on the relationship you have with your employer. Where I work (programmer in a small company < 20 employees), everybody knows each other. We can easily pitch ideas which are forwarded to our client when they find it interesting. I just have to mention it at some point, or send an informal mail. I don't have any experience how this would work in a big(ger) company, but perhaps you wouldn't be asking this question if you feel 'safe' suggesting this idea to your boss/supervisor.
You mention it are add-on features to existing business products. The natural questions is, are you working on this product? When you are, I don't see the harm in suggesting this, as chances are big you end up implementing it, or working together with people who are. The cost for the company is also smaller because you don't have to start working on a new product. If it's not a product you are working on, the company will likely feel hesitant to switch you to another product, as this causes a certain overhead, even in a small company.
Don't just expect your employer to hand the project to you, also convince him why you are up for the task, and at least ask for it while mentioning it.