Estimates of value are virtually impossible to provide without actually visually inspecting the note. As with almost all other collectibles, condition is usually a critical determining factor in the value of a particular note. SPMC cannot undertake appraisals of notes (you should contact a professional currency dealer to determine the value of notes).  Please do not send email attachments to us!  Numismatics (including coins, paper money, tokens, medals, and related material) is a broad and highly detailed body of objects.  Most collectors and even most dealers do not know about it all, even within the more restricted area of paper money.

Here are some suggestions how to get an opinion of the value of your notes:

• Check for coin/paper money dealers in your community and show the material to more than one dealer.  One national organization of dealers is the Professional Currency Dealers Association.  However, many reputable dealers are not members, and this is not an endorsement of PCDA.
• See if there is a local coin club in your area that you could contact to see if there are knowledgeable members who could give you opinions.  Remember, though, that most members will be coin collectors, and even the paper money collectors among them may not know your material.
• Check for coin/paper money shows in your areas.  One national calendar of shows is CoinZip.com.  Take the material to the show and ask several dealers for value opinions.
• If you have a large collection to evaluate, do not expect a detailed appraisal for free unless you are selling the material to the person doing the appraisal.

Here are some general observations on the most commonly encountered "odd looking" notes: 

• Silver Certificates – these small size (current size) notes are similar to today's Federal Reserve Notes except that they have blue treasury seals and serial numbers. In circulated condition, they carry only minimal premiums over face value. Some exceptions are replacement notes (which have a * as part of the serial number) and a few of the very early series, as well as notes with errors or special or fancy serial numbers. When in doubt, consult one of several price guides that are readily available.  
• United States Notes – these small size notes have red treasury seals and serial numbers and again command only modest premiums over face value if in circulated condition. $100's, particularly in uncirculated condition, do bring premiums over face value.  
• Silver Certificates stamped HAWAII or with a yellow treasury seal – these issues were used during World War II for use by American troops in the Pacific (HAWAII) and the Mediterranean theatre (yellow seal). These notes do have collector value over and above face value depending on condition and the denomination.  
• $1 Federal Reserve Notes signed by Joseph Barr (series 1963-B) – Legend has it that these notes are rare because Barr was in office for a very short period of time. The Bureau of Engraving and Printing continued to print these long after Barr left office, and these notes have no particular premium over face value if even minutely circulated.  
• Bank of the United States - $1,000 note – 1840 – serial number 8894 – This is a worthless modern reproduction produced in huge quantities as a gift shop curiosity and sales item. Any old paper money printed on parchment-like crinkled paper with printed signatures should be regarded with extreme suspicion (see this website on oldcurrencyvalues.com for a list of serial numbers employed on modern reproductions such as this).
• Confederate notes dated February 17, 1864 have modest collector premiums of $15 and more per note (if you're selling to a dealer) depending on condition and denomination; the $5, $10, and $20 denominations being the most common.

There are many other different types of currency which are collectible. If you aren’t sure what you have, seek a professional opinion. Understand that dealers need to make a living too and that purchase offers are generally between 50% (for more common material) and 75% of "retail."  Some notes, such as common circulated Silver Certificates, will be difficult to generate interest in simply due to a still plentiful supply and limited demand regardless of the "catalog value."