I've now invested in over 100 companies -- and there's not much I haven't seen before. Companies that I have seeded have raised over $1 billion in follow-on funding in later rounds... I take board seats when appropriate. More about value-add here - http://www.firstround.com/why/now_is_the_time
Describe what you have done, what you are doing, and the kinds of things you are interested in.