I know this place is full of people who know how to make sections for Google's 'personalized home', so here goes:

I've been looking for a section similar to the stock ticker, except for currencies, it shoud basically display any given number of specified currency conversion rates (easily done in google search by searching for "[amount] [currency] in [currency]")

Example (What mine would look like):

1 USD = 7.27 SEK
1 EUR = 9.36 SEK
1 GBP = 13.72 SEK

I reckon it should be fairly simple, all it does is submitting a query to google search, maybe client-side, truncates the result to two decimals and puts it on the personalized home box

Definitely doable, this module's XML could be a good basis:
http://googlemodules.com/module/17/

Might need 3 queries though... I'm not sure you can compress the queries (1 usd in sek) or (1 eur in sek) into a single query...