There are obviously many, many traits that make up effective team players in any group of co-workers. In my experience, the most effective characteristics are (1) the possession of a good sense of humour, (2) an easy-going disposition, (3) recognition of diversity and (4) the commitment to put in the hard yards.
(1) In my years in a very customer-centric role, the best workers, managers and people i have been able to respect most are those who can maintain chirpy throughout incredibly stressful situations, and also use their sense of humour to smooth over tense situations with both colleagues and customers. Having a couple of jokesters around makes the staff's time at work enjoyable, and 99% of the time, if the staff are happy the customers will be too!
(2) There will ALWAYS, in every workplace, be those who are easily offended, easily offensive, easily stressed, easily get angry with colleagues etc, but the teammates who shine are those who can rise above the politics of the workplace and form amicable, professional relationships with their co-workers.
(3) Recognition of diversity is similar to being easy-going, as it is simply acknowledging that some colleagues and customers will always be different to you, and will do things in their own way and own time and that your way isn't necessarily the only one. You might even be able to learn new tricks!
(4) This is very simple. No one likes a deadweight in their team, and a good work ethic, attention for detail, time management skills and efficiency all come under this banner and are essential in the functioning of any team in the workplace.
about where the brown liquid was coming from! But all was fixed when the oven was serviced... 
