diff --git a/lib/DDG/Goodie/Conversions.pm b/lib/DDG/Goodie/Conversions.pm
index 296c8fb792d..a166c170844 100755
--- a/lib/DDG/Goodie/Conversions.pm
+++ b/lib/DDG/Goodie/Conversions.pm
@@ -153,7 +153,6 @@ handle query => sub {
 
     return unless defined $result->{'result'};
 
-    # TODO: it's not clear what this does exactly. Come back and comment
     my $computable_factor = $styler->for_computation($factor);
     if (magnitude_order($computable_factor) > 2*$accuracy + 1) {
         $factor = sprintf('%g', $computable_factor);
diff --git a/share/goodie/conversions/conversions.js b/share/goodie/conversions/conversions.js
index e1a2d15bde3..cab419b017c 100644
--- a/share/goodie/conversions/conversions.js
+++ b/share/goodie/conversions/conversions.js
@@ -42,7 +42,7 @@ DDH.conversions = DDH.conversions || {};
         leftValue:  "",
         rightValue: "",
 
-        customUnits: [
+        customUnits: [          
             // CUSTOM AREA UNITS
             {name: 'barn',          factor: '0.00000000000000000000000000000001 hectare'},
             {name: 'rood',          factor: '0.10117141 hectare'},
@@ -51,6 +51,12 @@ DDH.conversions = DDH.conversions || {};
             {name: 'sqdecimeter',   factor: '0.000001 hectare'},
             {name: 'sqcentimeter',  factor: '0.0001 m2'},
             {name: 'sqmillimeter',  factor: '100 sqcentimeter'},
+     
+             // CUSTOM DURATION UNITS
+            {name: "femtosecond",   factor: "0.000000000000001 second"},
+            {name: "picosecond",    factor: "0.000000000001 second"},
+            {name: "fortnight",     factor: "2 week"},
+            {name: "siderealyear",  factor: "1.00001741 year"},
 
             // CUSTOM ENERGY UNITS
             {name: 'kilojoule', factor: '1000 joules'},
@@ -246,6 +252,10 @@ DDH.conversions = DDH.conversions || {};
                 { symbol: 'decade',         name: 'Decade' },
                 { symbol: 'century',        name: 'Century' },
                 { symbol: 'millennium',     name: 'Millennium' },
+                { symbol: 'femtosecond',    name: 'Femtosecond'},
+                { symbol: 'picosecond',     name: 'Picosecond'},
+                { symbol: 'fortnight',      name: 'Fortnight'},
+                { symbol: 'siderealyear',   name: 'Sidereal Year'},
             ],
             defaults: ['minute', 'second']
         },
diff --git a/share/goodie/conversions/triggers.yml b/share/goodie/conversions/triggers.yml
index a032e7e20b7..2c65e1075c7 100755
--- a/share/goodie/conversions/triggers.yml
+++ b/share/goodie/conversions/triggers.yml
@@ -605,6 +605,34 @@ type: duration
 unit: second
 symbols: [s]
 ---
+aliases:
+  - femtosecond
+  - femtoseconds
+  - femto second
+  - femto seconds
+  - fsecond
+  - fseconds
+type: duration
+unit: femtosecond
+---
+aliases:
+  - picosecond
+  - picoseconds
+  - pico second
+  - pico seconds
+  - psecond
+  - pseconds
+type: duration
+unit: picosecond
+---
+aliases:
+  - fortnight
+  - fortnights
+  - fort night
+  - fort nights
+type: duration
+unit: fortnight
+---
 aliases:
   - millisec
   - millisecs
@@ -685,6 +713,18 @@ type: duration
 unit: year
 symbols: [a]
 ---
+aliases:
+  - sidereal yr
+  - sidereal yrs
+  - sidereal year
+  - sidereal years
+  - side real yr
+  - side real yrs
+  - side real year
+  - side real years
+type: duration
+unit: siderealyear
+---
 aliases: 
   - decade
   - decades
diff --git a/spec/conversions_spec.js b/spec/conversions_spec.js
index 4ea91f228ce..ca41385074f 100644
--- a/spec/conversions_spec.js
+++ b/spec/conversions_spec.js
@@ -109,6 +109,24 @@ describe("Conversion of Custom Units", function() {
         expect(conversion).toEqual("5e+5");
     });
 
+    /**
+     * CUSTOM DURATION UNITS
+     */
+    it("should convert picoseconds to femtoseconds", function() { 
+        var conversion = stripUnit(math.eval("6picosecond to femtosecond"));
+        expect(conversion).toEqual("6000");
+    });
+
+    it("should convert fortnight to days", function() { 
+        var conversion = stripUnit(math.eval("2fortnight to day"));
+        expect(conversion).toEqual("28");
+    });
+
+    it("should sidereal years to years", function() { 
+        var conversion = stripUnit(math.eval("2siderealyear to year"));
+        expect(conversion).toEqual("2.00003482");
+    });
+
     /**
      * CUSTOM ENERGY UNITS
      */
diff --git a/t/Conversions.t b/t/Conversions.t
index b767ce504db..0fbb99b8f87 100755
--- a/t/Conversions.t
+++ b/t/Conversions.t
@@ -1449,6 +1449,30 @@ ddg_goodie_test(
 			physical_quantity => 'area'
 		})
 	 ),
+	'fortnight to days' => test_zci(
+		'', structured_answer => make_answer({
+			raw_input => '1',
+			from_unit => 'fortnight',
+			to_unit => 'day',
+			physical_quantity => 'duration'
+		})
+	 ),
+	'7 picoseconds to fseconds' => test_zci(
+		'', structured_answer => make_answer({
+			raw_input => '7',
+			from_unit => 'picosecond',
+			to_unit => 'femtosecond',
+			physical_quantity => 'duration'
+		})
+	 ),
+	'10 years to sidereal years' => test_zci(
+		'', structured_answer => make_answer({
+			raw_input => '10',
+			from_unit => 'year',
+			to_unit => 'siderealyear',
+			physical_quantity => 'duration'
+		})
+	 ),
 	'10 barns to cm2' => test_zci(
 		'', structured_answer => make_answer({
 			raw_input => '10',
@@ -1537,7 +1561,6 @@ ddg_goodie_test(
 			physical_quantity => 'frequency'
      })
 	 ),
-
 	 # natural language queries
 	 'unit converter' => test_zci(
 		 '',