If there has been one thing I have learned in preparing to go to Clarkson is that school is expensive [$37,000/year and increasing every year!] and that EVERY little bit counts.
I got the FIRST Scholarship through Clarkson [$6,000/year]
And the Achievement Award it my school which Clarkson honors [$9,000/year]
And then I got a local scholarship. [Amount TBD]
I found fastweb to be a good resource, although I do not know if I have recieved any of the 8 scholarships I have applied for. But hey, a little essay that could potentially give you $500 or more towards your education is worth it in my opinion.
And like Billfred said, always check with the financial aid office... they have ways of helping you get to the school you want to go to, you just have to put yourself out there.