Mostly brainstorming here. There are many uses for coins/tokens, but I havnt really seen anywhere which attempts to classify and categorize them.. maybe because only recently with stuff like CounterParty and MasterCoin have all of the potential uses theorized have actually become possible. So anyway, here is my attempt:
Currency / Point Tokens
These are the typical type of tokens most people know and understand (and use). Any token that acts as a currency, points or rewards system, or unit of account would fall under this category. This includes Bitcoin itself, alts such as Litecoin and Dogecoin (and all the rest). For the metacoin protocols, also includes things such as LTBcoin, Storjcoin (SJXC) and Folding Coin (FLDC)
An equity token is any token which represents stake/shares/ownership of company, website, organization, property (digital or physical) etc.. Everything from company shares, to property deeds on a house, to profit sharing from a website, or an investment scheme. Anything that represents a variable value in something, ownership, and/or pays out some sort of dividend. There are not many of these out there yet, but I think we will see a ton of them in the future. SWARM is one unique example of this on CounterParty
Redeemables are any tokens that can be sent back somewhere in order to receive some sort of product or service, digital or otherwise. This could be as simple as a token to receive 25% off your order, or buy 1 get 1 free (i.e, traditional coupon). It could be an advertising spot on a website, or sponsorship slot on a show or podcast. It can be 1 oz of gold, or even just an hour of someones time. Here on Lets Talk Bitcoin, we are already making use of redeemable tokens, and you will likely see a lot crop up over the coming months. Some examples (again, on counterparty, not aware of any others really) are LTBDISPLAY, HOURCONSULT (hour of consulting with @adam ;) ), SPONSOR, as well as initiatives by some others such as COINFIREAD (ad spot on the coinfire website) and BKEYCHAIN (redeemable for 1 bitcoin keychain). You can also get actual gold via buying GDTT tokens (run by Digital Tangible Trust)
Access tokens are a recent idea that has been developed over the past couple months (not sure if someone had already thought about it before.. probably). Our Token Societies service is one of the first implementations of the "Token Controlled Access" concept. It's been discussed on the show already, so I won't get into it with this post... but essentially its changing what you can access on a website (or game or w/e) based on what and how many tokens you have in a wallet you control. We are just getting started with this idea, but some example tokens are EARLY (gives access to the exclusive LTB founders forum), PODCAST (lets a user publish their own podcasts and create their own magic words) and STAFF (gives access to the staff only forum)
These are special tokens used for decentralized voting. In most cases, a couple different voting tokens are sent out to all holders of another existing token at a 1:1 ratio. Holders can then go and check out what the voting is all about and what the options are. Send whichever option token back, and on the deadline all votes received back can be counted to determine the groups decision. With counterparty, tokens can be made "callable", which means you can set it up so that after a certain date and time, you can call back all of the tokens back to your address, effectively ending the vote and allowing you to re-use the tokens. An example that SWARM has done was issuing out SWARMVOTEONE and SWARMVOTETWO tokens for some decisions a few months ago.
Name Squats / Junk Tokens
This one pretty much covers any tokens that have no real use at all. Typically ones that were made just for testing and messing around (I like to use WALMART tokens for testing :) ), but also ones that were created just for name squatting purposes (like whoever owns the asset named GOOGLE)
That's about all I can think of at the moment. Also a lot of tokens will probably overlap several categories, should be pretty interesting. Anyone think of any other potential types I might be missing?