I love getting emails! Here are a few categories of emails that I get that might help you frame your message (or save you the time of sending an email in the first place). If I don't get back to you within 48 hours and a response is needed, I've either flagged your email because I want to think about it some more, or occasionally I will have missed it by mistake. Feel free to follow up to check.
Can you be my advisor?
I do several types of advising: first-year advising, second-year advising (usually my first-year advisees from the previous year), concentration advising, honors thesis advising, Masters student advising, and Ph.D. student advising.
Each year, different faculty rotate in as first-year, second-year, or concentration advisors. If I'm doing first-year or second-year advising that year, usually I'll have 5-6 students for each year who are interested in eventually pursuing computer science. I also usually have about 20-30 concentration advisees. If I'm on the list that year, you can just choose me as an advisor and send me a note. If I'm not on the list, I'd be happy to serve as your advisor if there is a particular reason, like you want someone to talk to about UI/UX, human-computer interaction (HCI) research, or doing a startup. Otherwise, you're better off picking someone who is openly taking advisees that year. For honors thesis advising, I'm happy to advise projects broadly related to HCI research. For honors theses, Masters projects, and independent studies, I can either advise a project that you come up with, in which case we can meet about once a month and we can talk about how things are going; or you can join my research group and work on an existing project, in which case we'll meet about once a week. If you wish to do your own project, you should prepare a timeline for the semester, and a plan of what you will do. If you want to join my research group, see the question at the bottom of this page about exactly that.
Masters students and Ph.D. students are typically assigned advisors when they arrive in one way or another. You're welcome to ask to switch to me if you're interested in doing HCI research, but we should talk first.
If you're interested in applying for a Ph.D. at Brown and having me as your advisor, feel free to email about your interests and background. Generally, I will respond unless I feel like you're just copy-pasting the same message to many other faculty (these are pretty obvious, because they look like email templates). I have admitted Ph.D. students every year so far, but there may be future years where I might not admit any. But either way, I will consider Ph.D. students for admission every year. I will also occasionally serve as the advisor for RISD Masters students if they're doing work closely related to one of my research topics.
Can you write me a recommendation letter?
I'm happy to write recommendation letters. If I know you personally (like you have visited me in my office, or talked to me after class about what you're doing), then send me your other materials, and some bullet points of things you'd like me to include for that particular application, along with where to submit it and a deadline. If you've taken my class but I have never spoken to you, then I use my generic letter, which says that you were in my class, what grade you got and how that compares to other students, and what you did some your assignments. Please give me at least one week lead time before your deadline, because I write it in two passes -- once to outline the key things I want to say, and the second time to write it out in paragraphs. Also, I appreciate it when you let me know what eventually happened with your application, even if it was not successful. Finally, I'm often willing to send you a copy of the letter after I submit it, if you ask. I find that sometimes it helps to see what others write about you as a form of feedback.
Can I take your class?
For CSCI 1300 that I teach in the Fall, if you enrolled during pre-registration period (which I highly encourage), you're all set. If you're enrolling at the start of the semester and the course is already at its enrollment cap, there is an online application form for extra open spots so you can fill out. Take a look at the course website for details. If you're a RISD student, you're welcome to take my courses; take a look at the FAQ on the course website. For my graduate seminar that I teach in the spring, usually there's an online application form that you fill out for a spot. I'm on sabbatical for Spring 2017 so won't be teaching during that semester. There's no auditing or sitting in for my classes, but for CSCI 1300, if you did not enroll and just quietly sat in, I probably won't notice.
Can I come and meet with you?
Of course. Take a quick look at my busy/free times (I try to keep it up to date) to find some times that fit with your schedule, and are somewhat adjacent to my other busy times. My office is 407 on the fourth floor of the CIT. The best ways to meet with me is to send me an email with a couple of times where we're both free, and a sentence about what you want to talk about. Or you can come by during my office hours (changes every semester, but is posted on my website). You're also welcome to drop in whenever I'm in my office with my door open (how widely open my door is, is somewhat proportional to how open I am to being interrupted).
Can I join your research group?
Brown University students: I'm always looking for the right students to help with my group's research projects. I've written detailed account of the research experience and expectations, which you are highly encouraged to review. Take a look at our HCI research group website to see what projects are currently active, and let me know which ones you're particularly interested in. Each project requires a different skillset, so try to find ones that match yours, and fill out this form.
Non-Brown students: If you're a student at another university, it's quite hard for us to work together. I get a lot of requests from students outside the United States to travel here and join my research group, or do an "internship". I almost never consider these (even if you're self-funded) unless there is a perfect match in research interests and you already show you have some results doing research in HCI. I have had successful cases of working with students at another university in the United States who can't find an appropriate advisor in their own department, so I'm quite open to that. I have offered RISD students the chance to help out on a research project if there was a good fit, but it's never worked out because of the intense RISD workload.