Well, I finally made one. Ive been putting it off for a while, because so many of them already exist, but it provided the opportunity to look at information sorting in a more streamlined pattern. This Rib fabrication Rhino script allows the user to select a surface, input the row and column count, specify the rib dimensions, then sit back, have a coffee and let the computer do the work.

Option Explicit
'Script written by <David Mans>
'Adapted from concepts provided Andrew Payne of Lift Architects
'http://www.liftarchitects.com/
'Script adapted by <Neoarchaic Studio>
'Script version Thursday, April 02, 2009 12:47:23 AM

Call Main()
Sub Main()
	Dim surface, arrValue
	surface = Rhino.GetObject("Select Surface",8,True)
	If isNull(surface) Then Exit Sub
	Call reparameterize(surface)

	arrValue = Rhino.PropertyListBox(array("Columns","Rows","Rib Height","Rib Width","Tile Spacing","textHeight"),array(10,10,1,0.2,1,0.25))
	If isNull(arrValue) Then Exit Sub

	Call Rhino.EnableRedraw(False)
	Dim bBox: bBox = Rhino.BoundingBox(surface)
	Dim dist: dist = Rhino.Distance(bBox(0),bBox(4))

	Dim grid, ribs, draw
	grid = projectGrid(surface,CInt(arrValue(0)),CInt(arrValue(1)))
	ribs = makeRib(grid,CDbl(arrValue(2)),CDbl(arrValue(3)),dist)
	draw = makeDrawing(ribs(1),CDbl(arrValue(4)),CDbl(arrValue(5)))
	Call Rhino.DeleteObjects(grid(0))
	Call Rhino.DeleteObjects(grid(1))

	Call Rhino.EnableRedraw(True)
End Sub
Function projectGrid(surface,cols,rows)
	projectGrid = Null
	Dim i,j,k,r,s
	Dim bBox, order, edge(3)
	Dim tCrv,crv(1),pCrv(),arrCrv,dom(1), cStp(1)

	bBox = Rhino.BoundingBox(surface)
	order = array(4,5,7,6,4,7,5,6)

	r=0
	For i = 0 To 3 Step 1
		edge(i) = Rhino.AddLine(bBox(order(r)),bBox(order(r+1)))
		r = r+2
	Next
	order = array(cols,rows)
	r=0
	For i = 0 To 1 Step 1
		s=0
		dom(0) = Rhino.CurveDomain(edge(r))
		dom(1) = Rhino.CurveDomain(edge(r+1))
		cStp(0) = (dom(0)(1)-dom(0)(0))/order(i)
		cStp(1) = (dom(1)(1)-dom(1)(0))/order(i)
		For j = 0 To order(i)-1 Step 1
			tCrv = Rhino.AddLine(Rhino.EvaluateCurve(edge(r),dom(0)(0)+cStp(0)*0.5+cStp(0)*j),Rhino.EvaluateCurve(edge(r+1),dom(1)(0)+cStp(1)*0.5+cStp(1)*j))
			arrCrv = Rhino.ProjectCurveToSurface(tCrv,surface,Rhino.VectorReverse(Rhino.WorldXYPlane()(3)))
			Call Rhino.DeleteObject(tCrv)
			For k = 0 To uBound(arrCrv) Step 1
				ReDim Preserve pCrv(s)
				pCrv(s) = arrCrv(k)
				s = s+1
			Next
		Next
		crv(i) = pCrv
		r=r+2
	Next
	Call Rhino.DeleteObjects(edge)
	projectGrid = crv
End Function
Function makeRib(curves,height,width,zHeight)
	makeRib = Null
	Dim i,j,k,r
	Dim intersect, tPt
	Dim arrObject()
	Dim blnBlock, xVal, yVal, zVal, tPts(7)

	xVal = array(-width*0.5,-width*0.5,width*0.5,width*0.5)
	yVal = array(-width*0.5,width*0.5,width*0.5,-width*0.5)
	zVal = array(0,height*2+zHeight)
	r=0
	For i = 0 To 1 Step 1
		For j = 0 To 3 Step 1
			tPts(r) = array(xVal(j),yVal(j),zVal(i))
			r=r+1
		Next
	Next
	blnBlock = Rhino.AddBox(tPts)

	r=0
	For i = 0 To uBound(curves(0)) Step 1
		For j = 0 To uBound(curves(1)) Step 1
			intersect = Rhino.CurveCurveIntersection(curves(0)(i),curves(1)(j))
			If isNull(intersect) Then
			Else
				ReDim Preserve arrObject(r)
				tPt = intersect(0,1)
				arrObject(r) = Rhino.CopyObject(blnBlock,array(0,0,0),tPt)
				r=r+1
			End If
		Next
	Next

	Dim tRib, rib(), tCurve()
	Dim ribSet(1), cutRibs(1),tLine(1),ribCurve(1)

	tLine(0) = Rhino.AddLine(array(0,0,0), array(width,0,0))
	tLine(1) = Rhino.AddLine(array(0,0,0), array(0,width,0))

	For i = 0 To 1 Step 1
		ReDim rib(uBOund(curves(i)))
		For j = 0 To uBOund(curves(i)) Step 1
			Call Rhino.AddTextDot(i & "-" & j,Rhino.CurveEndPoint(curves(i)(j)))
			tRib = Rhino.ExtrudeCurveStraight(curves(i)(j),array(0,0,0),array(0,0,height))
			Call Rhino.MoveObject(tRib,Rhino.CurveEndPoint(tLine(i)),Rhino.CurveMidPoint(tLine(i)))
			rib(j) = Rhino.ExtrudeSurface(tRib,tLine(i))
			Call Rhino.DeleteObject(tRib)
		Next
		ribSet(i) = rib
	Next

	For i = 0 To 1 Step 1
		ReDim tCurve(uBound(ribSet(i)))
		If i = 0 Then
			Call Rhino.MoveObjects(arrObject,array(0,0,0),array(0,0,height*0.5))
		Else
			Call Rhino.MoveObjects(arrObject,array(0,0,0),array(0,0,-height*2-zHeight))
		End If
		cutRibs(i) = Rhino.BooleanDifference(ribSet(i),arrObject,False)
		For j = 0 To ubound(cutRibs(i)) Step 1
			tCurve(j) = Rhino.ProjectCurveToSurface(curves(i)(j),cutRibs(i)(j),Rhino.VectorReverse(Rhino.WorldXYPlane()(3)))(0)
		Next
		ribCurve(i) = tCurve
		Call Rhino.DeleteObjects(ribSet(i))
	Next

	Call Rhino.DeleteObjects(arrObject)
	Call Rhino.DeleteObjects(tLine)
	Call Rhino.DeleteObject(blnBlock)
	makeRib = array(cutRibs,ribCurve)
End Function
Function makeDrawing(arrCrvs,spacing,tHeight)
	makeDrawing = Null
	Dim i,j
	Dim cPlane, wPlane, bBox, tObject(), objects()
	ReDim objects(uBOund(arrCrvs))

	Dim pPt, tPt
	Dim xPos, yPos, tPos, ySet()

	For i = 0 To uBound(arrCrvs) Step 1
		ReDim tObject(uBound(arrCrvs(i)))
		For j = 0 To uBound(arrCrvs(i)) Step 1
			cPlane = Rhino.CurvePlane(arrCrvs(i)(j))
			wPlane = Rhino.WorldXYPlane()
			tObject(j) = Rhino.OrientObject(arrCrvs(i)(j),array(cPlane(0),Rhino.PointAdd(cPlane(0),cPlane(1)),Rhino.PointAdd(cPlane(0),cPlane(2))),array(wPlane(0),wPlane(1),wPlane(2)))
			bBox = Rhino.BoundingBox(tObject(j))
			Call Rhino.MoveObject(tObject(j),bBox(0),array(0,0,0))
		Next
		objects(i) = tObject
	Next
	yPos = 0
	For i = 0 To uBound(arrCrvs) Step 1
		tPos = 0
		xPos = 0
		ReDim ySet(uBound(arrCrvs(i)))
		For j = 0 To uBound(arrCrvs(i)) Step 1
			bBox = Rhino.BoundingBox(objects(i)(j))
			pPt = array(xPos,yPos,0)
			If j > 0 Then
				tPos = xPos
				xPos = tPos+Rhino.Distance(bBox(0),bBox(1))+spacing
			Else
				xPos = bBox(1)(0)+spacing
			End If
			Call Rhino.MoveObject(objects(i)(j),bBox(0),pPt)
			Call Rhino.AddText(i & "-" & j,Rhino.CurveStartPoint(objects(i)(j)),tHeight)
			ySet(j) = bBox(2)(1)
		Next
		yPos = Rhino.Max(ySet)+spacing
	Next
End Function
Function reparameterize(strCurveID)
	If Rhino.IsCurve(strCurveID) = True Then
		Call rhino.SelectObject(strCurveID)
		Call rhino.Command("reparameterize 0 1")
		Call rhino.UnselectAllObjects()
	End If
	If Rhino.IsSurface(strCurveID) = True Then
		Call rhino.SelectObject(strCurveID)
		Call rhino.Command("reparameterize 0 1 0 1")
		Call rhino.UnselectAllObjects()
	End If
End Function