With the socialiser, this is the key. The system has to contain a way for them to socialise and build relationships.

Status can lead to more relationships. Think about twitter. If you become "famous", gain some sort of status for being influential in a topic, you open the doors for more people to find you and build relationships.

There needs to be a way to to find people, whether it is based on leaderboards (so who the "experts are"), or suggestions based on similar interestes. A social system that does not allow you to find others or be found, will fail.

Working together requires the formation of relationships. The very nature of collaboration means that communication will be key.

Some may not agree with this. However, I have created close relationships based on competeing with people in a friendly way. There are unique social opportunities to be had when working in a team and competing against other teams - the relationships can build in both camps!

Give the the user the ability to make the environment feel like it is theirs. Let them customise everything they can, from their representation in the system, to the wallpaper in their virtual workspace.

Encourage this free expression with the ability to unlock content. This could be through exploration of the system, or competitions or just for exhibiting desired behaviours in the system.

Let the user choose their path through the system, again you are trying to encourage exploration and a feeling of freedom and autonomy.

Encourage creativity, this could come in the form of tools that allow users to create anything from graphics to documents. The idea is to again allow freedom here.

Back to exploration, easter eggs are a fun way to reward a user for just having a look around.

One of the key elements for an achiever is the feeling that they are on the road towards mastery. Levels and goals help to map a users progression through a system.

Again, all part of the road to mastery.  Quests give the user a fixed goal to achieve. Challenges give them something to overcome, to get that feeling of real achievement long before they have reached mastery. Balanced use of these can keep an achiever engaged for a long time - but they are hard to keep fresh.

These can both help a user track progress and achievement. Rather than being the purpose of participating, they are recognition of successful participation. This is an important distinction. The ability to display them should be available, though not all will want to - it can be a very personal thing.

Another form of recognition and progress tracking. Those at the top of a well designed leaderboard are generally those who are achieving the most at something. This is not for everyone though, many will find leaderboards de-motivating, especially those at the bottom. Use with care!

What better way to prove you are mastering something, than to take on others who are of similar skill levels to you. Again, not for everyone, but for some this kind of activity can be fun and rewarding.

This user type is motivated by the feeling of purpose and meaning. A system that allows them to give to others is essential. This can come in the form of material gifting of items (covered below), or giving of themselves. Knowledge sharing, mentoring, helping others.

Social status gives a philanthropist the opportunity to be discovered by more people that they can help. It is not status to feel important, it is to guide people towards them. You can't help people if they don't know you can help.

Access to more abilities in a system gives a philanthropist more ways to help others and to contribute. As a moderator of a forum, they will help "police" a system for the benefit of the other users. As an editor, they will help to make sure that quality of the content is as good as possible.

If your system uses some kind of rewards, give the philanthropist the option to use them for the good of others. It could be the ability to donate them to others to help them achieve something. It could be that you allow them to trade the rewards for charitable donations.

Working together with others is not just attractive to socialisers. Philanthropists in a team have the opportunity to help others directly, with content creation, mentoring, leadership, support etc.