Conferences suitable for undergraduates

• Young Mathematicians Conference, Ohio State University, August 28 - August 30, 2009.
  Funding available. Plenary speakers: Laura DiMarco, Carolyn Gordon, Peter Sarnak. Deadline for applications: August 3.
• Millikin Undergraduate Mathematics Research Conference, Saturday, October 3, 2009, Decatur, IL.
  Key note speaker: Dr. Michael Axtell (Univ. of St. Thomas).
  Registration deadline: September 28.
• Undergraduate Mathematics Day, University of Dayton (Ohio), November 7, 2009.
  Plenary speakers: Thomas Santner (Ohio Statue), Kristin Duncan (San Diego State).
  Seems to be focusing on the statistics/applied side.
• Shenandoah Undergraduate Mathematics Conference, October 3, 2009, James Madison University, Harrisonburg, Virginia
  Funding very limited. Judging from past years' program, the conference seems to be targeted mostly at local or regional students.
• Conference on Undergraduate Research in Mathematics, Nov. 20-21, 2009, Penn State University. A very well run conference at a major research university. Funding available and quite generous. Plenty of slots for 15-minute student talks. Deadline for submission of abstracts Nov. 10.
• Joint Mathematical Meetings, January 13 - 16, 2010, San Francisco.
  Huge meeting of the three leading mathematics organizations (AMS, MAA, SIAM). Poster sessions for undergraduate students.
  Abstract Submission Page for Poster Session. (Deadline November 6, 2009.)
• MAA (Mathematical Association of America) MathFest, Summer 2010.
  The annual summer meeting of the MAA (one of the leading math societies), with hundreds of speakers, sessions, workshops, etc., and a Pi Mu Epsilon session for undergraduate talks (with generous funding available). The above page links to this year's (2009) meeting, which was in Portland, Oregon.
• Nebraska Conference for Undergraduate Women in Mathematics, January 29 - 31, 2010, Univ. of Nebraska, Lincoln.
  A highly regarded one-of-a-kind conference founded by a UIUC PhD alumn (Judy Walker).
  
• Rose-Hulman Undergraduate Mathematics Conference, March 2010.
  A well run conference with a long history (going back 25 years) at one the best undergraduate institutions for mathematics. Rose-Hulman has a strong tradition in fostering undergraduate research, publishes an undergraduate mathematics journal (Rose-Hulman Journal for Undergraduate Mathematics) and runs a highly regarded Summer REU program.