This article, The Lesson is to Network, Business Week (5/13/05) is geared for small businesses generally and not solos specifically, but the ideas are equally applicable.  Here are two of my favorite suggestions from Nancy Michaels in this interview-style article:

Q: What are some marketing essentials?

A: If you can only have two things I’d say get an identity package
together and invest in this kind of marketing material. Have a Web site
and a great business card that offers something of value that people
will keep. I am a fan of top 10 lists. For instance, if you are a
pediatrician, have a business card that on the back says three things
that will keep your kids safe.

This type of list approach would work for lawyers too – and it’s something that I’ve never seen done before.

Michaels also describes how she took advantage of a creative but risky marketing opportunity

of the best things I ever did was to bid on a silent auction lunch with
the CEO of Office Depot [Bruce Nelson] at a success strategies
conference in 2002. It cost me $1,000, but I had a meeting and ended up
getting Office Depot (ODP ) as a client. It was the most expensive
lunch I ever had, but I am now going into my third year with Office
Depot and it is my largest account.

I’m not sure how
frequently chances like that arise.  But the story bears out that if
you have a chance to get a meeting with a decision maker, take it –
because it just may pay off big time.