What are good professions for a druid?

Note: These are in no order of usefulness to a druid, but are just some of the many options.

1) Alchemy/Herbalism
With alchemy and herbalism you can cultivate herbs and make powerful potions. These potions can range from a simple healing potion to a potion that adds +2000 mana for 2 hours. Alchemists can specialize into either transmutation, elixers, or potions. Depending on your specialization and access to materials, there is a good deal of profit to be made here. Alchemy allows you to live longer and do more damage in battle, and also makes you a core asset of any guild.

2) Herbalism/Skinning/Mining (two gathering skills)
Druids are the best gatherers in the game. We can use stealth, travel form, flight form, and soothe animal to get in close to resource nodes. If you take two gathering skills you will be able to make a lot of money, and can always drop one later.

3) Mining/Engineering
Engineering can be used by any class, and gives you the ability to make some pretty cool items; some of which even work while shapeshifted.

4) Skinning/Leatherworking (Tribal Leatherworking/Elemental Leatherworking/Dragon Leatherworking)
Since we can wear leather, leatherworking is a great skill to have. Skinning is also great for making money. Leatherworking allows you to make many very useful items that will make character progression easier. It branches into tribal, elemental, and dragon leatherworking at 225+ skill. Tribal is best suited for druids, elemental for rogues, and dragon for shaman/hunter.

4) Enchanting
Druids make for great enchanters because we can do stealth runs of instances, skipping past the trash and killing only bosses. This makes leveling enchanting a lot easier

5) Other options
There are many other options, but I'm lazy! For more information on professions, see the following forum:

http://forums.worldofwarcraft.com/board.html?forumId=11116

What about secondary skills?
Learn them all! There is no limit, so why aren't you learning them?