Any good sell-side trading simulators?

Based on the most helpful WSO content, there's a market making simulator that you might find interesting. It's designed to get you thinking about bid-ask and moving your spreads. Here's the link: http://live.marketsims.com/TSDemo/

However, it's worth noting that this simulator might not fully meet your needs as it lacks the aspect of asymmetric information and interaction with other people, which are crucial in real trading scenarios.

As for creating your own simulator in Excel, it's definitely possible! In fact, one of the WSO users mentioned they were planning to create a simulator in Excel that's more geared towards helping students practice the arbs that come up in open outcry.

Remember, the key elements you'd want to incorporate in your simulator would be some level of uncertainty, market makers, a final payoff level where everything is settled, and asymmetric info. Also, don't forget to brush up on your quick mental maths skills - they'll come in handy!

And hey, if you're feeling adventurous, you could even turn this into a fun game with your friends. Who said learning can't be fun, right?

Sources: Converting an S&T Internship, S&T Intern Excel Knowledge, Is it possible to buy your way into Harvard MBA?, Q&A: Sell Side Equity Research to Software Engineer