Now you can install a free Sambahsa dictionary on your computer!

For example, here is GoldenDict on Linux:

GoldenDict can also be installed on Microsoft Windows.

If you are a Mac OSX Lion user, you can use the Mac OSX Dictionary:

Doing so allows you to see definitions of words in the Safari web browser simply by right-clicking a word and choosing "Look up <word> ":

Installation Instructions

Microsoft Windows

1. Download and install the free GoldenDict program from here: http://goldendict.org/download.php
2. Download the Sambahsa-English dictionary in StarDict format from here: Sambahsa-Dictionary-in-StarDict-format-20120415.zip
3. Unzip (extract) the file you downloaded in step 2; this will create a directory with the same name as that file but without the .zip extension.
4. Start up your GoldenDict program, and choose "Edit -- Dictionaries" then click the "Add" button. Select the directory you created in step 3 (select the actual directory folder, not the files inside it) and click the "Open" button. Finally click "Okay". The Sambahsa-English directory is now loaded into your GoldenDict program and you can go ahead and start using the dictionary.

Alternatively, you can use the Sambahsa-English dictionary in StarDict format with any dictionary software which can import StarDict dictionaries. Depending on which dictionary software you choose to use, you may be able to get pop-up definitions by right-clicking (for example this works with GoldenDict and Microsoft Word). Explore the features of whichever dictionary application you choose to use.

Mac OSX Lion

1. Download the Sambahsa-English dictionary in Mac OSX Lion Dictionary format from here: sambahsa-english-dic.dictionary.zip
2. Unzip (extract) the file you downloaded in step 1; this will create a file with the same name but without the .zip extension. 
3. Start up the Mac OSX Dictionary program (by clicking "Dictionary.app" in your Applications folder)
4. In the Dictionary program, select "File -- Open Dictionaries Folder"; a Finder window will open, showing you the dictionaries you already have installed (each dictionary is represented by a file ending in the .dictionary extension)
5. Copy the sambahsa-english-dic.dictionary file (which you unzipped in step 2) into your dictionaries folder (which you opened in step 4).
6. Quit your Dictionary program.
7. Restart your Dictionary program. Your Sambahsa-English dictionary is now loaded into you Mac OSX Dictionary. You will be able to right-click words to get convenient pop-up definitions in Safari and some other applications (this does not work in Firefox).

Alternatively, you can use either the StarDict format or the Mac OSX Lion Dictionary format files in any dictionary software which supports one or both of those formats. For example, the sambahsa-english-dic.dictionary file also works very well with TranslateIt!. GoldenDict is not available on Mac.

Linux

1. Install the free GoldenDict program using the package manager appropriate for your flavour of Linux (search for "goldendict"). Contrary to the advice given on the GoldenDict website, there is no need to compile from source; binaries appear to be widely available.
2. Download the Sambahsa-English dictionary in StarDict format from here: Sambahsa-Dictionary-in-StarDict-format-20120415.zip
3. Unzip (extract) the file you downloaded in step 2; this will create a directory with the same name as that file but without the .zip extension.
4. Start up your GoldenDict program, and choose "Edit -- Dictionaries" then click the "Add" button. Select the directory you created in step 3 (select the actual directory folder, not the files inside it) and click the "Open" button. Finally click "Okay". The Sambahsa-English directory is now loaded into your GoldenDict program and you can go ahead and start using the dictionary.

Alternatively, you can use the Sambahsa-English dictionary in StarDict format with any dictionary software which can import StarDict dictionaries. Depending on which dictionary software you choose to use, you may be able to get pop-up definitions by right-clicking (for example this works with GoldenDict and Microsoft Word). Explore the features of whichever dictionary application you choose to use.