Got a Helios 44-2. Nice lens. Pretty old (serial number may imply it's from 1979), but in decent condition; $30 shipped. It had a lot of dust and marks on both the front and rear elements, but they were very easily cleaned with MagicFiber-brand microfiber cloth which, frankly, lives up to its name - the thing is magical. (I got mine from Amazon; cheaper knockoffs may scratch the glass, so I wanted a reputable source.)

But it has fungus after the front element.

How do I open it up to get at it?

Unscrewing or removing the front element can be done in one of two ways. One, I believe you can disassemble the entire lens, and remove the front element from the inside components. Two, you can unscrew the front element directly. Some source suggest putting rubber (like from a burst balloon) onto the element and using a cap to apply pressure and unscrew. But it has grooves for a reason (see at 3 O'clock and 9 O'clock):

Technically speaking, one can use a simple screwdriver and some force to unscrew the front element. However, that has a high chance of slipping! And then your glass has a brand new scratch on it. Bad.

The tool you want is called a Lens Spanner Wrench. You can get one from Amazon or from Ebay. I chose to get mine from Ebay, and got a Arc (curved) lens spanner wrench, since I think it'll do a better job.

I wrote this article because it took me ages to figure out the name of the tool I was looking for!

Credit www.aliexpress.com

Update 11/4/13: It worked. Here's a picture taken with the now fungus-free lens:

And some close-up shots showing no more fungus:

Now, that front element was screwed on tight. There is no way I would have gotten it off without this wonderful tool. Good luck!

(Disclaimer: If you break your lenses, not my fault.)