Many institutions will only fund conference attendance (travel, fees & accommodation) if you can show it is worthwhile you attending. Oral presentation is normally a given (good PR for you and the institution). Presenting a poster is viewed as a chance to present a topic overview & network with like-minded people (though the actual exposure is questionable). Running a workshop gets you involved with people in your field & stimulates debate. You can also bill funding to a linked project budget.
Guest lectures and oral papers however are limited & draw fierce competition, so your chances of acceptance are reduced. So, my question is where does your funding normally come from & how do you justify your cause ?