My son and I are traveling to Germany this summer and we want to visit Finland to attend a wedding. What is the cheapest way to get to Helsinki from Germany?

German Wings or V-Bird most likely, both around €65 - €70, depending on where in Germany. See http://www.whichbudget.com for a good guide to low-cost European airlines.

Apart from the airlines Gardyloo suggested, there is also a new SAS affiliate called Blue 1. I recently read that they will take up a service from Hamburg to Helsinki this spring, which is not yet listed on their website, though. But you might want to watch this.

http://www.blue1.com/en/

You might also take a look at the Finnish national carrier Finnair

http://www.finair.com

A travel agency specializing in flights in Germany is Travel Overland.
I have used them a couple of times and was very satisfied with the rates they found me.
You will get a good overview of available flights and prices from their website. "Von" means "From" and "Nach" is "To".

http://www.travel-overland.com

If you have a little more time, you might consider travelling by ferry, which is fairly enjoyable, actually to my experience.
Silja Line offers a route from Rostock in Germany to Tallinn, Estonia. You will have to disembark their "Finnjet" Ferry (which almost features cruiseship standards) there but will leave half an hour later on a fast ferry from Tallinn for the short trip across the Gulf of Finland.

http://www.silja.fi/PRICES/One-way%2...;x=11&y=11

From Travemuende close to Luebeck, Finnlines offer a (slower) service. Their ferries are mainly freight service oriented, but feature pretty luxurious cabins.

http://www.ferrycenter.fi/finnlines/en/
index.shtml

Finally, from Rostock, the Greek ferry operator "Superfast" offers nonstop service with pretty new ships to Hanko in Finland. I believe they have a bus service from there to Helsinki.

http://www.superfastferries.de/Balti...=Prices%202004

I suppose, I would have a first look on that Travel-Overland website, followed by checking the others according to your travel preferences.

Enjoy your trip!

Another option might be to fly Estonian Air (modern aircraft like 737) into Tallinn and then take a speed ferry across the Gulf.

Estonian Air is currently advertising fares of € 57.- from Hamburg and Berlin into Tallinn and (I believe) € 77.- from Frankfurt. They fly (unlike V-Bird) out of the normal airports and might thus be equally convenient. Besides (if you plan enough time) the Old Town of Tallinn is really picturesque.

Thank you for all the great info. This will really help me plan the trip!

Forgot to include a link to Estonian Air in case you decide to fly through Tallinn.

http://www.estonian-air.ee

It's available in English language, too.